0-1 Integer Programming

0-1 Knapsack Problem

01 Matrix

1-bit and 2-bit Characters

1-indexed Array

132 Pattern

2 Keys Keyboard

24 Game


3Sum Closest

3Sum Smaller

3Sum With Multiplicity

4 Keys Keyboard


4Sum II

A Number After a Double Reversal

A Strategy For Developing Insight

A* algorithm

Abbreviating the Product of a Range

Absolutely Convergent Series

Abstract Model at Five Levels

Abstract Representation

Abstraction at Five Levels

Abstraction Concept Analysis Diagram

Accessing Environment Variables in Rails

Account Balance After Rounded Purchase

Accounts Merge

Accumulate Absolute Differences

Accumulate Coding Construct

Accumulate Concatenation

Accumulate Count

Accumulate Differences

Accumulate Division

Accumulate Maximum

Accumulate Maximum and Minimum

Accumulate Minimum

Accumulate Power

Accumulate Product

Accumulate XOR

Action Items for Developing Your Toolbox

Active Engagement in Problem Solving

Active Learning Strategies

Activity-Selection Problem

Acyclic List

Add a Sequence of Numbers

Add Adjacent Elements

Add Binary

Add Bold Tag in String

Add Digits

Add Edges to Make Degrees of All Nodes Even

Add Minimum Number of Rungs

Add One Row to Tree

Add Strings

Add to Array-Form of Integers

Add Two Numbers

Add Two Numbers II

Add Two Polynomials Represented as Linked Lists

Adding Spaces to a String

Adding Two Negabinary Numbers

Additive Number

Adjacency List

Adjacency Matrix

Adjacent Element Comparison

Advantage Shuffle

Affinity Category

Airplane Seat Assignment Probability

Alert Using Same Key-Card Three or More Times in a One Hour Period

Alien Dictionary

All Ancestors of a Node in a Directed Acyclic Graph

All Divisions With the Highest Score of a Binary Array

All Elements in Two Binary Search Trees

All Nodes Distance K in Binary Tree

All O`one Data Structure

All Paths from Source Lead to Destination

All Paths From Source to Target

All Possible Full Binary Trees

All-Pairs Shortest-Paths Problem

Allocate Mailboxes

Alphabet Board Path

Alphabetical Order

Alternating Digit Sum

Ambiguous Coordinates

Amount of New Area Painted Each Day

Amount of Time for Binary Tree to Be Infected

Anagram Checker

Analogical Reasoning Concept Analysis Diagram

Analysis Phase

Analytical Reasoning Concept Analysis Diagram

Analyze Constraints

Analyze User Website Visit Pattern

Android Unlock Patterns

Angle Between Hands of a Clock

Animation Programming

Anonymous Function at Five Levels

Append Characters to String to Make Subsequence

Append K Integers With Minimal Sum

Appendix A

Apply Bitwise Operations to Make Strings Equal

Apply Discount Every n Orders

Apply Discount to Prices

Apply Operations to an Array

Apply Operations to Make All Array Elements Equal to Zero

Apply Operations to Maximize Score

Approximation Algorithm

Approximation by Integrals

Arithmetic Series

Arithmetic Slices

Arithmetic Slices II - Subsequence

Arithmetic Subarrays

Armstrong Number

Arranging Coins

Array Basics

Array Negation Updates

Array Nesting

Array of Doubled Pairs

Array Partition

Array Transformation

Array Transformation Problem

Array With Elements Not Equal to Average of Neighbors

Arrow Function Comparison

Arrow Function in Javascript at Five Levels

Art of Problem-Solving: Leveraging Abstract Models for Effective Solutions

As Far from Land as Possible

Assign Cookies

Associative Relationship at Five Levels

Asteroid Collision

async and wait in 5 Levels

Asynchronous in Javascript at Five Levels

Augment a Data Structure

Automating SSH Key Generation for Secure Server Access

Autopoiesis at Five Levels

Autopoietic Optimum at Five Levels

Available Captures for Rook


Average Height of Buildings in Each Segment

Average of Levels in Binary Tree

Average Salary Excluding the Minimum and Maximum Salary

Average Value of Even Numbers That Are Divisible by Three

Average Waiting Time

AVL Tree

Avoid Flood in The City

Avoiding the Hammer Syndrome: Versatility in Problem-Solving for Programmers

Axiom at Five Levels


Backspace String Compare

Backtracking at Five Levels

Backtracking Sequence

Backtracking with Dynamic Programming

Bag of Tokens

Balance a Binary Search Tree

Balanced Binary Tree

Barcode Scanner

Base 7

Baseball Game

Basic Calculator

Basic Calculator II

Basic Calculator III

Basic Drills

BasicCalculator IV

Basics of Lexicographic, Dictionary, and Alphabetic Ordering

Battleships in a Board

Beautiful Arrangement

Beautiful Arrangement II

Beautiful Array

Beautiful Pairs

Before and After Puzzle

Best Meeting Point

Best Poker Hand

Best Position for a Service Centre

Best Practices in NextJS

Best Practices in React

Best Sightseeing Pair

Best Team With No Conflicts

Best Time to Buy and Sell Stock

Best Time to Buy and Sell Stock II

Best Time to Buy and Sell Stock II

Best Time to Buy and Sell Stock III

Best Time to Buy and Sell Stock IV

Best Time to Buy and Sell Stock with Cooldown

Best Time to Buy and Sell Stock with Transaction Fee

Bezout's Identity

Big Countries

Big O Analysis of Algorithms

Bijection Relationship

Bin Packing

Binary Gap

Binary Number with Alternating Bits

Binary Prefix Divisible By 5

Binary Search

Binary Search Template

Binary Search Tree Iterator

Binary Search Tree Iterator II

Binary Search Tree to Greater Sum Tree

Binary Search Trees

Binary Search Variant

Binary Searchable Numbers in an Unsorted Array

Binary String With Substrings Representing 1 To N

Binary Subarrays With Sum

Binary Tree Cameras

Binary Tree Coloring Game

Binary Tree Inorder Traversal

Binary Tree Level Order Traversal

Binary Tree Level Order Traversal II

Binary Tree Longest Consecutive Sequence

Binary Tree Longest Consecutive Sequence II

Binary Tree Maximum Path Sum

Binary Tree Paths

Binary Tree Postorder Traversal

Binary Tree Preorder Traversal

Binary Tree Pruning

Binary Tree Right Side View

Binary Tree Tilt

Binary Tree Upside Down

Binary Tree Vertical Order Traversal

Binary Tree Zigzag Level Order Traversal

Binary Trees With Factors

Binary Watch

Binding in JavaScript at Five Levels

Binomial Coefficient

Bisect Left in Python

Bit Masking

Bit Vector

Bitonic Sequence

Bitset Strategy to Find Missing Elements

Bitwise AND of Numbers Range

Bitwise OR of All Subsequence Sums

Bitwise ORs of Subarrays

Bitwise XOR of All Pairings

Block in JavaScript

Block Scope in Javascript at Five Levels

Block vs Function Scope in Javascript

Boats to Save People

Bold Words in String

Bomb Enemy

Booking Concert Tickets in Groups

Bottom Up Dynamic Programming vs Top Down Dynamic Programming

Boundary of Binary Tree

Bounding Summations

Bounding the Terms

Brace Expansion

Brace Expansion II

Branch and Bound

Breadth-First Search Function for Graph Object

Break a Palindrome

Breath First Traversal

Brick Wall

Bricks Falling When Hit

Bridging the Gap Between Human Intelligence and Artifical Intelligence

Brightest Position on Street

Broken Calculator

Bubble Sort

Bucket Count

Bucket Sort

Bucket Sort Variant

Buddy Strings

Build a Matrix With Conditions

Build an Array With Stack Operations

Build Array from Permutation

Build Array Where You Can Find The Maximum Exactly K Comparisons

Build Binary Expression Tree From Infix Expression

Building a Mathematical Model

Building Boxes

Buildings With an Ocean View

Bulb Switcher

Bulb Switcher II

Bulls and Cows

Burst Balloons

Bus Routes

Business Logic in React

Buy Two Chocolates

Calculate Amount Paid in Taxes

Calculate Delayed Arrival Time

Calculate Digit Sum of a String

Calculate Money in Leetcode Bank

Call Stack in JavaScript at Five Levels

Callback in JavaScript at Five Levels

Camelcase Matching

Campus Bikes

Campus Bikes II

Can Convert String in K Moves

Can I Win

Can Make Arithmetic Progression From Sequence

Can Make Palindrome from Substring

Can Place Flowers

Can You Eat Your Favorite Candy on Your Favorite Day?


Candy Crush

Capacity of a Vertex

Capacity To Ship Packages Within D Days

Capitalize the Title

Car Fleet

Car Fleet II

Car Pooling

Card Flipping Game

Cartesian Coordinate System Scan Conversion

Cartesian Product

Cartesian Tree

Cat and Mouse

Cat and Mouse II

Catalan Number

Categorize Box According to Criteria

Causal Reasoning

Ceiling of x

Cells in a Range on an Excel Sheet

Cells with Odd Values in a Matrix

Chalkboard XOR Game

Champagne Tower

Change Minimum Characters to Satisfy One of Three Conditions

Change the Root of a Binary Tree

Cheapest Flights Within K Stops

Check Array Formation Through Concatenation

Check Completeness of a Binary Tree

Check Distances Between Same Letters

Check Duplicates

Check for Contradictions in Equations

Check How Long a Process is Running

Check If a Number Is Majority Element in a Sorted Array

Check if a Parentheses String Can Be Valid

Check If a String Can Break Another String

Check If a String Contains All Binary Codes of Size K

Check If a String Is a Valid Sequence from Root to Leaves Path in a Binary Tree

Check if a String Is an Acronym of Words

Check If a Word Occurs As a Prefix of Any Word in a Sentence

Check If All 1's Are at Least Length K Places Away

Check if All A's Appears Before All B's

Check if All Characters Have Equal Number of Occurrences

Check if All the Integers in a Range Are Covered

Check if an Array Is Consecutive

Check if an Original String Exists Given Two Encoded Strings

Check if Array is Good

Check if Array Is Sorted and Rotated

Check If Array Pairs Are Divisible by k

Check if Binary String Has at Most One Segment of Ones

Check if Every Row and Column Contains All Numbers

Check If It Is a Good Array

Check If It Is a Straight Line

Check if it is Possible to Split Array

Check if Matrix Is X-Matrix

Check if Move is Legal

Check If N and Its Double Exist

Check if Number Has Equal Digit Count and Digit Value

Check if Number is a Sum of Powers of Three

Check if Numbers Are Ascending in a Sentence

Check if One String Swap Can Make Strings Equal

Check if Pangram

Check if Point Is Reachable

Check If String Is a Prefix of Array

Check if String Is Decomposable Into Value-Equal Substrings

Check If String Is Transformable With Substring Sort Operations

Check if The Number is Fascinating

Check if There is a Path With Equal Number of 0's And 1's

Check if There Is a Valid Parentheses String Path

Check if There is a Valid Partition For The Array

Check if There is a Valid Path in a Grid

Check If Two Expression Trees are Equivalent

Check If Two String Arrays are Equivalent

Check if Word Can Be Placed In Crossword

Check if Word Equals Summation of Two Words

Check If Word Is Valid After Substitutions

Check Knight Tour Configuration

Check Whether Two Strings are Almost Equivalent

Checking Existence of Edge Length Limited Paths

Checking Existence of Edge Length Limited Paths II

Cherry Pickup

Cherry Pickup II

Choice of Datastructure for N Queens Problem

Choose Edges to Maximize Score in a Tree

Choose Numbers From Two Arrays in Range

Choosing between var, let and const in Javascript

Cinema Seat Allocation

Circle and Rectangle Overlapping

Circular Array Loop

Circular Increment

Circular Linked List

Circular Permutation in Binary Representation

Circular Sentence

Class in JavaScript at Five Levels

Classes More Than 5 Students

Climbing Stairs

Clone Binary Tree With Random Pointer

Clone Graph

Clone N-ary Tree

Closest Binary Search Tree Value

Closest Binary Search Tree Value II

Closest Dessert Cost

Closest Divisors

Closest Fair Integer

Closest Leaf in a Binary Tree

Closest Node to Path in Tree

Closest Nodes Queries in a Binary Search Tree

Closest Prime Numbers in Range

Closest Room

Closest Subsequence Sum

Closures - Inner and Outer Functions in JavaScript

Cloud-init Tasks

Clumsy Factorial

Coding Blog using Hugo

Coin Change

Coin Change II

Coin Collection

Coin Path

Collatz Sequence

Collect Coins in a Tree

Collecting Chocolates

Color the Triangle Red

Coloring A Border

Column-Major Order


Combination Sum

Combination Sum II

Combination Sum III

Combination Sum IV


Combinatorial Optimization at Five Levels

Combine Two Tables

Command to Merge My Branch

Common Mistakes Made During Coding Interviews

Comparator Function

Compare Exchange Operation

Compare Strings by Frequency of the Smallest Character

Compare Version Numbers

CompareToAll Function

CompareToMax Function

Complement of Base 10 Integer

Complete Binary Tree Inserter

Complex Number Multiplication

Component Communication in React

Components and HTML DOM

Compositeness of a Number

Computationally Intractable Problems

Computer Model at Five Levels

Computer Science - The Mechanization of Abstraction

Computing a Minimum Spanning Tree in Undirected Graph

Concatenate and Alternate

Concatenated Words

Concatenation of Array

Concatenation of Consecutive Binary Numbers

Concept Analysis Diagram for Iteration

Concept Analysis Diagram for Loop Control Variables

Concept Analysis Diagram for Loop Invariant

Concept Analysis Diagram for Recursion

Concept Analysis Diagram Template

Conceptual Model at Five Levels

Concrete Thinking

Concretization Concept Analysis Diagram

Concurrency in JavaScript at Five Levels

Confidence Interval in Statistics

Confusing Number

Confusing Number II

Connecting Cities With Minimum Cost

Consecutive Available Seats

Consecutive Characters

Consecutive Numbers

Consecutive Numbers Sum

Constrained Subsequence Sum

Constraint Satisfaction Problems

Constraints and Time Complexity

Constraints at Five Levels

Construct Binary Search Tree from Preorder Traversal

Construct Binary Tree from Inorder and Postorder Traversal

Construct Binary Tree from Preorder and Inorder Traversal

Construct Binary Tree from Preorder and Postorder Traversal

Construct Binary Tree from String

Construct K Palindrome Strings

Construct Quad Tree

Construct Smallest Number From DI String

Construct String from Binary Tree

Construct String With Repeat Limit

Construct Target Array With Multiple Sums

Construct the Lexicographically Largest Valid Sequence

Construct the Longest New String

Construct the Rectangle

Contain Virus

Container With Most Water

Contains Duplicate

Contains Duplicate II

Contains Duplicate III

Contiguous Array

Continuous Subarray Sum

Continuous Subarrays

Converging Series

Convert 1D Array Into 2D Array

Convert 1D index to 2D

Convert a Number to Hexadecimal

Convert an Array Into a 2D Array With Conditions

Convert Binary Number in a Linked List to Integer

Convert Binary Search Tree to Sorted Doubly Linked List

Convert BST to Greater Tree

Convert Integer to the Sum of Two No-Zero Integers

Convert JSON String to Object

Convert Sorted Array to Binary Search Tree

Convert Sorted List to Binary Search Tree

Convert the Temperature

Convert to Base -2

Convex Polygon

Convolution of Vector

Coordinate With Maximum Network Quality

Copy List with Random Pointer

Copying Elements from One Array to Another

Corporate Flight Bookings

Correct a Binary Tree

Count All Possible Routes

Count All Valid Pickup and Delivery Options

Count Anagrams

Count and Say

Count Array Pairs Divisible by K

Count Artifacts That Can Be Extracted

Count Asterisks

Count Binary Substrings

Count Collisions of Monkeys on a Polygon

Count Collisions on a Road

Count Common Words With One Occurrence

Count Complete Subarrays in an Array

Count Complete Tree Nodes

Count Days Spent Together

Count Different Palindromic Subsequences

Count Distinct Numbers on Board

Count Elements With Strictly Smaller and Greater Elements

Count Equal and Divisible Pairs in an Array

Count Fertile Pyramids in a Land

Count Good Meals

Count Good Nodes in Binary Tree

Count Good Numbers

Count Good Triplets

Count Good Triplets in an Array

Count Hills and Valleys in an Array

Count Houses in a Circular Street

Count Houses in a Circular Street II

Count Increasing Quadruplets

Count Integers in Intervals

Count Integers With Even Digit Sum

Count Items Matching a Rule

Count Largest Group

Count Lattice Points Inside a Circle

Count Length of a Number

Count Negative Numbers in a Sorted Matrix

Count Nice Pairs in an Array

Count Nodes Equal to Average of Subtree

Count Nodes Equal to Sum of Descendants

Count Nodes That Are Great Enough

Count Nodes With the Highest Score

Count Number of Bad Pairs

Count Number of Distinct Integers After Reverse Operations

Count Number of Homogenous Substrings

Count Number of Maximum Bitwise-OR Subsets

Count Number of Nice Subarrays

Count Number of Pairs With Absolute Difference K

Count Number of Possible Root Nodes

Count Number of Rectangles Containing Each Point

Count Number of Special Subsequences

Count Number of Teams

Count Number of Texts

Count Number of Ways to Place Houses

Count Numbers with Unique Digits

Count Odd Numbers in an Interval Range

Count of Integers

Count of Matches in Tournament

Count of Range Sum

Count of Smaller Numbers After Self

Count Operations to Obtain Zero

Count Pairs in Two Arrays

Count Pairs of Equal Substrings With Minimum Difference

Count Pairs Of Nodes

Count Pairs Of Similar Strings

Count Pairs Whose Sum is Less than Target

Count Pairs With XOR in a Range

Count Palindromic Subsequences

Count Paths That Can Form a Palindrome in a Tree

Count Positions on Street With Required Brightness

Count Prefixes of a Given String

Count Primes

Count Servers that Communicate

Count Sorted Vowel Strings

Count Special Integers

Count Special Quadruplets

Count Square Submatrices with All Ones

Count Square Sum Triples

Count Stepping Numbers in Range

Count Strictly Increasing Subarrays

Count Student Number in Departments

Count Sub Islands

Count Subarrays With Fixed Bounds

Count Subarrays With Median K

Count Subarrays With More Ones Than Zeros

Count Subarrays With Score Less Than K

Count Submatrices With All Ones

Count Substrings That Differ by One Character

Count Substrings with Only One Distinct Letter

Count Substrings Without Repeating Character

Count Subtrees With Max Distance Between Cities

Count the Digits That Divide a Number

Count the Hidden Sequences

Count the Number of Beautiful Subarrays

Count the Number of Complete Components

Count the Number of Consistent Strings

Count the Number of Fair Pairs

Count the Number of Good Subarrays

Count the Number of Good Subsequences

Count the Number of Ideal Arrays

Count the Number of K-Big Indices

Count the Number of K-Free Subsets

Count the Number of Square-Free Subsets

Count the Number of Vowel Strings in Range

Count The Repetitions

Count Total Number of Colored Cells

Count Triplets That Can Form Two Arrays of Equal XOR

Count Unguarded Cells in the Grid

Count Unhappy Friends

Count Unique Characters of All Substrings of a Given String

Count Univalue Subtrees

Count Unreachable Pairs of Nodes in an Undirected Graph

Count Vowel Strings in Ranges

Count Vowel Substrings of a String

Count Vowels Permutation

Count Ways To Build Good Strings

Count Ways to Build Rooms in an Ant Colony

Count Ways to Distribute Candies

Count Ways to Group Overlapping Ranges

Count Ways to Make Array With Product

Count Words Obtained After Adding a Letter

Count Zero Request Servers

Count Zeroes in an Array


Counting Bits

Counting Distinct Special Subsequences with Maximum Frequency Sum

Counting Duplicates in a Sorted Array

Counting Elements

Counting Inversion

Counting Potential Attack Vectors in Network Keys Based on Queries

Counting Sort

Counting Words With a Given Prefix

Couples Holding Hands

Course Schedule

Course Schedule II

Course Schedule III

Course Schedule IV

Course Structure Based on Bloom's Taxonomy

Cousins in Binary Tree

Cousins in Binary Tree II

Cracking the Safe

Crawler Log Folder

Create a Cloudinit File

Create Binary Tree From Descriptions

Create Components With Same Value

Create Maximum Number

Create Sorted Array through Instructions

Create Target Array in the Given Order

Critical Connections in a Network

Cross Comparison

Cross Product of Vector

Cryptography in Five Levels

Cube Counting


Cue Direction

Curated List of Top 75 LeetCode

Curly Braces in JavaScript

Currency Arbitrage

Currying at Five Levels

Custom Data Store

Custom Sort String

Customer Placing the Largest Number of Orders

Customers Who Never Order

Cut Off Trees for Golf Event

Cut Them All

Cutting Ribbons

Cycle Detection

Cycle Length Queries in a Tree

Cyclic List

Cyclic Replacement

Cyclic Sort

Cyclically Rotating a Grid

Daily Temperatures

Data is Code. Code is Data.

Data Stream as Disjoint Intervals

Data Transformation

Day of the Week

Day of the Year

Dealing with Dead Code in React

Decimal to Binary

Decision Problem

Decision Tree and Recursion

Decision Trees

Decision-Tree Model in Sorting Algorithms

Declarative vs Imperative at Five Levels

Decode String

Decode the Message

Decode the Slanted Ciphertext

Decode Ways

Decode Ways II

Decode XORed Array

Decode XORed Permutation

Decoded String at Index

Decoding NP-Hard Problems: A Guide from Simple to Complex Understanding

Decoding Polynomial Time: A Complexity Explained at Five Levels

Decomposition at Five Levels

Decompress Run-Length Encoded List

Decrease and Conquer at Five Levels

Decrease Elements To Make Array Zigzag

Decremental String Concatenation

Decrypt String from Alphabet to Integer Mapping

Deduce New Constraints

Deductive Reasoning

Deepest Leaves Sum

Defanging an IP Address

defer in Javascript at Five Levels

Defuse the Bomb

Degree of an Array

Delete a Local Git Branch

Delete and Earn

Delete Characters to Make Fancy String

Delete Columns to Make Sorted

Delete Columns to Make Sorted II

Delete Columns to Make Sorted III

Delete Duplicate Emails

Delete Duplicate Folders in System

Delete Greatest Value in Each Row

Delete Leaves With a Given Value

Delete N Nodes After M Nodes of a Linked List

Delete Node in a BST

Delete Node in a Linked List

Delete Node in BST

Delete Nodes And Return Forest

Delete Operation for Two Strings

Delete the Middle Node of a Linked List

Delete Tree Nodes

Delivering Boxes from Storage to Ports

Department Highest Salary

Department Top Three Salaries

Deployment Parser

Depth First Traversal

Depth of BST Given Insertion Order

Describe the Painting

Design a File Sharing System

Design a Food Rating System

Design A Leaderboard

Design a Number Container System

Design a Stack With Increment Operation

Design a Text Editor

Design a Todo List

Design Add and Search Words Data Structure

Design an ATM Machine

Design an Expression Tree With Evaluate Function

Design an Ordered Stream

Design Authentication Manager

Design Bitset

Design Browser History

Design Cancellable Function

Design Circular Deque

Design Circular Queue

Design Compressed String Iterator

Design Excel Sum Formula

Design File System

Design Front Middle Back Queue

Design Graph With Shortest Path Calculator

Design HashMap

Design HashSet

Design Hit Counter

Design In-Memory File System

Design Linked List

Design Log Storage System

Design Memory Allocator

Design Most Recently Used Queue

Design Movie Rental System

Design Parking System

Design Phone Directory

Design Search Autocomplete System

Design Skiplist

Design Snake Game

Design SQL

Design Tic-Tac-Toe

Design Twitter

Design Underground System

Design Video Sharing Platform

Destination City

Destroy Sequential Targets

Destroying Asteroids

Destructuring in JavaScript

Detect Anagrams

Detect Capital

Detect Cycle in a Directed Graph

Detect Cycle in an Undirected Graph

Detect Cycles in 2D Grid

Detect Pattern of Length M Repeated K or More Times

Detect Squares

Detecting Cycle in a Linked List

Determine Color of a Chessboard Square

Determine if String Halves Are Alike

Determine if Two Events Have Conflict

Determine if Two Strings Are Close

Determine the Minimum Sum of a k-avoiding Array

Determine the Winner of a Bowling Game

Determine Whether Matrix Can Be Obtained By Rotation

Detonate the Maximum Bombs

DI String Match

Diagonal Traverse

Diagonal Traverse II

Diameter of Binary Tree

Diameter of N-Ary Tree

Dice Roll Simulation

Diet Plan Performance

Difference Between Element Sum and Digit Sum of an Array

Difference Between Maximum and Minimum Price Sum

Difference Between Ones and Zeros in Row and Column

Difference Check

Difference of Element and Index

Difference of Number of Distinct Values on Diagonals

Different Ways to Add Parentheses

Digit Count in Range

Dinner Plate Stacks

Disconnect Path in a Binary Matrix by at Most One Flip

Discover Your Ideal Learning Trajectory to Learn Programming Quickly

Disjoint-Set Data Structure

Display Table of Food Orders in a Restaurant

Distance Between Bus Stops

Distance to a Cycle in Undirected Graph

Distant Barcodes

Distinct Echo Substrings

Distinct Numbers in Each Subarray

Distinct Prime Factors of Product of Array

Distinct Subsequences

Distinct Subsequences II

Distinct Substrings

Distinguishing Between Problem Restatement and Abstract Representation in Problem-Solving

Distribute Candies

Distribute Candies to People

Distribute Coins in Binary Tree

Distribute Money to Maximum Children

Distribute Repeating Integers

Diverging Series

Divide a String Into Groups of Size k

Divide and Conquer at Five Levels

Divide Array in Sets of K Consecutive Numbers

Divide Array Into Equal Pairs

Divide Array Into Increasing Sequences

Divide Chocolate

Divide Intervals Into Minimum Number of Groups

Divide Nodes Into the Maximum Number of Groups

Divide Players Into Teams of Equal Skill

Divide Two Integers



Division and Sum Digits

Divisor Game

Domain Reduction

Domino and Tromino Tiling

Dot Product of Two Sparse Vectors

Dota2 Senate

Double a Number Represented as a Linked List

Doubly Linked List Basics

Drill Sequence

Drills Catalog

Dungeon Game

Duplicate Adjacent

Duplicate Elements

Duplicate Emails

Duplicate Zeros

Dynamic Array

Dynamic Programming at Five Levels

Earliest Possible Day of Full Bloom

Edit Distance

Efficiently Identifying Timed-Out Requests from Large Log Files

Egg Drop With 2 Eggs and N Floors

Eight Queens Problem

Element Appearing More Than 25% In Sorted Array

Elements in Array After Removing and Replacing Elements

Eliminate Maximum Number of Monsters

Elimination Game

Emergence at Five Levels

Empirical Rule at Five Levels

Employee Bonus

Employee Free Time

Employee Importance

Encode and Decode Strings

Encode and Decode TinyURL

Encode N-ary Tree to Binary Tree

Encode Number

Encode String with Shortest Length

Encrypt and Decrypt Strings

Encrypted Words


Equal Rational Numbers

Equal Row and Column Pairs

Equal Sum Arrays With Minimum Number of Operations

Equal Tree Partition

Erect the Fence

Erect the Fence II

ES6 Function Enhancements

Escape a Large Maze

Escape The Ghosts

Escape the Spreading Fire

Euclid's Algorithm

Euler Tour

Eulerian Path

Evaluate Boolean Binary Tree

Evaluate Division

Evaluate Reverse Polish Notation

Evaluate the Bracket Pairs of a String

Even Number

Even Odd Tree

Exam Room

Excel Sheet Column Number

Excel Sheet Column Title

Exclusive Time of Functions

Execution Context in JavaScript at Five Levels

Execution of All Suffix Instructions Staying in a Grid

Exhaustive Enumeration at Five Levels

Existence of Brute Force Solution

Existence Proof in Computer Science


Expression Add Operators

Expression Evaluation in JavaScript

Expressions and Side Effects in JavaScript

Expressions and Statements in JavaScript

Expressions in JavaScript

Expressive Words

External Sorting

Externalize the Information

Extra Characters in a String

Extract Digits

Extract Kth Character From The Rope Tree

Extracting Insights from a Problem Statement

Extremal Principle at Five Levels

Factor Combinations


Factorial Trailing Zeroes


Fair Candy Swap

Fair Distribution of Cookies

Fair Distribution of Cookies Q&A

Falling Squares

Fancy Sequence

Faulty Keyboard

Faulty Sensor

Feasibility Problem

Fibonacci Number

Fibonacci Sequence

Filling Bookcase Shelves

Filter Restaurants by Vegan-Friendly, Price and Distance

Final Prices With a Special Discount in a Shop

Final Value of Variable After Performing Operations

Find a Corresponding Node of a Binary Tree in a Clone of That Tree

Find a Good Subset of the Matrix

Find a Pair with Sum K by Traversing Sorted Array Forwards and Backwards

Find a Pair with Sum K in an Unsorted Array Using Hashtable

Find a Peak Element II

Find a Value of a Mysterious Function Closest to Target

Find All Anagrams in a String

Find All Duplicates in an Array

Find All Good Indices

Find All Good Strings

Find All Groups of Farmland

Find All K-Distant Indices in an Array

Find All Lonely Numbers in the Array

Find All Numbers Disappeared in an Array

Find All Palindromes

Find All People With Secret

Find All Possible Recipes from Given Supplies

Find All The Lonely Nodes

Find Anagram Mappings

Find And Replace in String

Find and Replace Pattern

Find Array Given Subset Sums

Find Bottom Left Tree Value

Find Center of Star Graph

Find Closest Node to Given Two Nodes

Find Closest Number to Zero

Find Common Characters

Find Consecutive Integers from a Data Stream

Find Critical and Pseudo-Critical Edges in Minimum Spanning Tree

Find Cumulative Salary of an Employee

Find Customer Referee

Find Distance in a Binary Tree

Find Duplicate File in System

Find Duplicate Subtrees

Find Elements in a Contaminated Binary Tree

Find Eventual Safe States

Find First and Last Position of Element in Sorted Array

Find First Palindromic String in the Array

Find Good Days to Rob the Bank

Find Greatest Common Divisor of Array

Find if Path Exists in Graph

Find in Mountain Array

Find K Closest Elements

Find K Pairs with Smallest Sums

Find K-Length Substrings With No Repeated Characters

Find K-th Smallest Pair Distance

Find Kth Bit in Nth Binary String

Find Kth Largest XOR Coordinate Value

Find Largest Value in Each Tree Row

Find Latest Group of Size M

Find Leaves of Binary Tree

Find Longest Awesome Substring

Find Lucky Integer in an Array

Find Maximal Uncovered Ranges

Find Maximum Number of String Pairs

Find Median from Data Stream

Find Median Given Frequency of Numbers

Find min and max in a binary search tree

Find Min and Max in a Single Scan Using Comparison and Assignment

Find Minimum in Rotated Sorted Array

Find Minimum in Rotated Sorted Array II

Find Minimum Time to Finish All Jobs

Find Minimum Time to Finish All Jobs II

Find Missing Elements

Find Missing Elements - Unsorted

Find Missing Observations

Find Mode in Binary Search Tree

Find N Unique Integers Sum up to Zero

Find Nearest Point That Has the Same X or Y Coordinate

Find Nearest Right Node in Binary Tree

Find Numbers with Even Number of Digits

Find Original Array From Doubled Array

Find Palindrome With Fixed Length

Find Peak Element

Find Permutation

Find Pivot Index

Find Players With Zero or One Losses

Find Positive Integer Solution for a Given Equation

Find Resultant Array After Removing Anagrams

Find Right Interval

Find Root of N-Ary Tree

Find rotation point

Find Score of an Array After Marking All Elements

Find Servers That Handled Most Number of Requests

Find Shortest Path with K Hops

Find Smallest Common Element in All Rows

Find Smallest Letter Greater Than Target

Find Subarrays With Equal Sum

Find Subsequence of Length K With the Largest Sum

Find Substring With Given Hash Value

Find Target Indices After Sorting Array

Find the Array Concatenation Value

Find the Celebrity

Find the City With the Smallest Number of Neighbors at a Threshold Distance

Find the Closest Marked Node

Find the Closest Palindrome

Find the Derangement of An Array

Find the Difference

Find the Difference of Two Arrays

Find the Distance Value Between Two Arrays

Find the Distinct Difference Array

Find the Divisibility Array of a String

Find the Duplicate Number

Find the Highest Altitude

Find the Index of the First Occurrence in a String

Find the Index of the Large Integer

Find the K-Beauty of a Number

Find the K-Sum of an Array

Find The K-th Lucky Number

Find the Kth Largest Integer in the Array

Find the Kth Smallest Sum of a Matrix With Sorted Rows

Find the Longest Balanced Substring of a Binary String

Find the Longest Equal Subarray

Find the Longest Semi-Repetitive Substring

Find the Longest Substring Containing Vowels in Even Counts

Find the Longest Valid Obstacle Course at Each Position

Find the Losers of the Circular Game

Find the Maximum Achievable Number

Find the Maximum Divisibility Score

Find the Maximum Number of Marked Indices

Find the Middle Index in Array

Find the Minimum and Maximum Number of Nodes Between Critical Points

Find the Minimum Number of Fibonacci Numbers Whose Sum Is K

Find the Most Competitive Subsequence

Find The Original Array of Prefix Xor

Find the Pivot Integer

Find the Prefix Common Array of Two Arrays

Find the Punishment Number of an Integer

Find the Safest Path in a Grid

Find the Score of All Prefixes of an Array

Find the Shortest Superstring

Find the Smallest Divisor Given a Threshold

Find the String with LCP

Find the Student that Will Replace the Chalk

Find the Substring With Maximum Cost

Find the Town Judge

Find the Value of the Partition

Find the Width of Columns of a Grid

Find the Winner of an Array Game

Find the Winner of the Circular Game

Find Three Consecutive Integers That Sum to a Given Number

Find Triangular Sum of an Array

Find Two Non-overlapping Sub-arrays Each With Target Sum

Find Unique Binary String

Find Valid Matrix Given Row and Column Sums

Find Winner on a Tic Tac Toe Game

Find Words That Can Be Formed by Characters

Find XOR Sum of All Pairs Bitwise AND

Find Xor-Beauty of Array

Finding 3-Digit Even Numbers

Finding a Path in a Matrix with Obstacles and Superpower

Finding Duplicates in a Sorted Array

Finding Duplicates in an Unsorted Array Using Counter and Adjacent Element Comparison

Finding MK Average

Finding Pairs With a Certain Sum

Finding the Length of the Last Word in a String

Finding the Number of Visible Mountains

Finding the Users Active Minutes

Finite Arithmetic Progression

First Bad Version

First Class Function at Five Levels

First Class Object at Five Levels

First Completely Painted Row or Column

First Day Where You Have Been in All the Rooms

First Letter to Appear Twice

First Missing Positive

First Order Statistic

First Principles Thinking Concept Analysis Diagram

First Unique Character in a String

First Unique Number

Fixed Point

Fizz Buzz

Flatten 2D Vector

Flatten a Multilevel Doubly Linked List

Flatten Binary Tree to Linked List

Flatten Nested List Iterator

Flattening Doubly Linked List

Flip Binary Tree To Match Preorder Traversal

Flip Columns For Maximum Number of Equal Rows

Flip Equivalent Binary Trees

Flip Game

Flip Game II

Flip String to Monotone Increasing

Flipping an Image

Flood Fill

Floor of x

Flower Planting With No Adjacent

Fold and Find

Form Array by Concatenating Subarrays of Another Array

Form Largest Integer With Digits That Add up to Target

Form Smallest Number From Two Digit Arrays

Forming the Longest Palindrome by Concatenating Array Strings

Forward and Backward Passes

Forward Checking

Four Divisors

Four Stages in Skills Progression

Fraction Addition and Subtraction

Fraction to Recurring Decimal

Frayer Model

Frayer Model for Abstraction

Freedom Trail

Frequency Counting

Frequency of the Most Frequent Element

Frequency Sort

Frequency Tracker

Friend Requests I: Overall Acceptance Rate

Friend Requests II: Who Has the Most Friends

Friends Of Appropriate Ages

Frog Jump

Frog Jump II

Frog Position After T Seconds

Fruit Into Baskets

Function Composition in JavaScript at Five Levels

Function Declaration vs Function Expression in JavaScript

Function Expression in JavaScript

Function Generating Problem

Function Generating Problems

Function Invocation and Method Invocation in JavaScript

Function Reference in JavaScript at Five Levels

Function Scope in Javascript at Five Levels

Functional Programming at Five Levels

Functional Programming in JavaScript

Functional Programming Ruby vs JavaScript

Functions are objects in JavaScript

Functions as Data in JavaScript

Functions as Values in JavaScript

Functions in Javascript

Fundamentals of Computer Algorithms: A Comprehensive Guide

Furthest Building You Can Reach

Game of Life

Game of Nim

Game Play Analysis I

Game Play Analysis II

Game Play Analysis III

Game Play Analysis IV

Gas Station

Gaussian Distribution


GCD Sort of an Array

Generalized Abbreviation

Generate a String With Characters That Have Odd Counts

Generate Combinations

Generate Parentheses

Generate Random Point in a Circle

Generating Function

Geometric Series

Get Biggest Three Rhombus Sums in a Grid

Get Equal Substrings Within Budget

Get Highest Answer Rate Question

Get Maximum in Generated Array

Get the Maximum Score

Get the Remote Branch

Get Watched Videos by Your Friends

Gitworkflow with Cloud-init

Global and Local Inversions

Global Object in JavaScript

Goal Parser Interpretation

Goat Latin

Gödel's Incompleteness Theorem

Granularity of Reuse

Graph Coloring

Graph Connectivity Testing

Graph Connectivity With Threshold

Graph Valid Tree

Gray Code

Greatest Common Divisor of Strings

Greatest Common Divisor Traversal

Greatest English Letter in Upper and Lower Case

Greatest Sum Divisible by Three

Greedy Approach

Grid Game

Grid Illumination

Grid Traversal Basics

Group Anagrams

Group Shifted Strings

Group the People Given the Group Size They Belong To

Groups of Special-Equivalent Strings

Groups of Strings

Grumpy Bookstore Owner

Guess Number Higher or Lower

Guess Number Higher or Lower II

Guess the Majority in a Hidden Array

Guess the Word

Guessing Game


H-Index II

Half of a Square

Hamiltonian Cycle

Hamiltonian Path

Hamming Distance

Hand of Straights

Handling Sum Queries After Update

Handshakes That Don't Cross

Happy Number

Harmonic Series

Harnessing the Power of Problem Reduction in Algorithm Design


Heapsort Algorithm


Height Checker

Height of Binary Tree After Subtree Removal Queries

Height of Special Binary Tree

Heuristics and Problem Space Reduction: Unraveling Complex Challenges


High Five

Higher Order Functions in Javascript at Five Levels

History of Mathematics

Hoisting in JavaScript at Five Levels

Horner's Rule

House Robber

House Robber II

House Robber III

House Robber IV

How Many Apples Can You Put into the Basket

How Many Numbers Are Smaller Than the Current Number

How to Acquire Coding Skills

How to Choose the Right Algorithm

How to Develop Your Own Toolbox for Solving Coding Problems

How to Develop Your Pattern Recognition Skills

How to Think Recursively

HTML Entity Parser

Human Traffic of Stadium

Ideal Approach to Learning to Code

Identical Values

Image Overlap

Image Smoother

Immutability Helper

Implement a Graph using Adjacency List

Implement Magic Dictionary

Implement Queue using Stacks

Implement Rand10() Using Rand7()

Implement Stack using Queues

Implement Trie (Prefix Tree)

Implement Trie II (Prefix Tree)

Implementing a HashTable with Simple Hashing Functions

Implementing a Queue using Array

Implementing a Stack using Array

Implementing an ArrayList from Scratch

In Place Sorting

Increasing Decreasing String

Increasing Order Search Tree

Increasing Triplet Subsequence

Increasing Triplet Subsequence

Increment Submatrices by One

Incremental Memory Leak

Incremental Method

Independent Subproblems

Induction Principle at Five Levels

Inductive and Deductive Reasoning

Inductive Reasoning

Influential Figures in Computer Science

Inorder Successor in BST

Inorder Successor in BST II

Inplace Modification

Inplace Reverse of an Array

Insert Delete GetRandom O(1)

Insert Delete GetRandom O(1) - Duplicates allowed

Insert Greatest Common Divisors in Linked List

Insert Interval

Insert into a Binary Search Tree

Insert into a Sorted Circular Linked List

Insertion Sort

Insertion Sort List

Insight and Expertise in Problem Solving

Insufficient Nodes in Root to Leaf Paths

Integer Break

Integer Linear Program

Integer Replacement

Integer to English Words

Integer to Roman

Integrating and differentiating series

Interactive Visualization

Interleaving String

Interpreted Language at Five Levels

Intersection of Multiple Arrays

Intersection of Three Sorted Arrays

Intersection of Two Arrays

Intersection of Two Arrays II

Intersection of Two Linked Lists

Interval List Intersections

Interval Tree

Intervals Between Identical Elements

Interview Questions

Invalid Transactions

Invariance Principle at Five Levels

Invariant and Loop Invariant

Invariant in Computer Science at Five Levels

Invariant vs Loop Invariant in Computer Science

Inversion of Array

Invert Binary Tree

Investments in 2016

Invocation Context in JavaScript at Five Levels



is Array a Preorder of Some ‌Binary Tree

Is Graph Bipartite?

Is Subsequence

Island Perimeter

Isomorphic Strings

Isomorphism of a Problem

Iteration vs Recursion

Iterator for Combination

ith Order Statistic

Javascript Closure in Five Levels

JavaScript Functions are Closures

Jewels and Stones

Join Two Arrays by ID

Josephus Problem

Jump Game

Jump Game II

Jump Game III

Jump Game IV

Jump Game V

Jump Game VI

Jump Game VII

Jump Game VIII

K Closest Points to Origin

K Divisible Elements Subarrays

K Empty Slots

K Highest Ranked Items Within a Price Range

K Inverse Pairs Array

K Items With the Maximum Sum

K Radius Subarray Averages

K-Concatenation Maximum Sum

K-diff Pairs in an Array

K-Similar Strings

K-th Smallest in Lexicographical Order

K-th Smallest Prime Fraction

K-th Symbol in Grammar


Keep Multiplying Found Values by Two

Keep Track of Last Duplicate in a Variable

Keyboard Row

Keys and Rooms

Kids With the Greatest Number of Candies

Kill Process

Knight Dialer

Knight Probability in Chessboard

Knowledge Gap Finder

Koko Eating Bananas

Kth Ancestor of a Tree Node

Kth Distinct String in an Array

Kth Largest Element in a Stream

Kth Largest Element in an Array

Kth Largest Sum in a Binary Tree

Kth Missing Positive Number

Kth Smallest Element in a BST

Kth Smallest Element in a Sorted Matrix

Kth Smallest Instructions

Kth Smallest Number in Multiplication Table

Kth Smallest Product of Two Sorted Arrays

Kth Smallest Subarray Sum

Ladder of Abstraction Concept Analysis Diagram

Lambda in JavaScript at Five Levels

Larger Expressions in JavaScript

Largest 1-Bordered Square

Largest 3-Same-Digit Number in String

Largest BST Subtree

Largest Color Value in a Directed Graph

Largest Combination With Bitwise AND Greater Than Zero

Largest Component Size by Common Factor

Largest Divisible Subset

Largest Element in a List

Largest Element in an Array after Merge Operations

Largest Local Values in a Matrix

Largest Magic Square

Largest Merge Of Two Strings

Largest Multiple of Three

Largest Number

Largest Number After Digit Swaps by Parity

Largest Number After Mutating Substring

Largest Number At Least Twice of Others

Largest Odd Number in String

Largest Palindrome Product

Largest Palindromic Number

Largest Perimeter Triangle

Largest Plus Sign

Largest Positive Integer That Exists With Its Negative

Largest Rectangle in Histogram

Largest Subarray Length K

Largest Submatrix With Rearrangements

Largest Substring Between Two Equal Characters

Largest Sum of Averages

Largest Time for Given Digits

Largest Triangle Area

Largest Unique Number

Largest Values From Labels

Last Day Where You Can Still Cross

Last Moment Before All Ants Fall Out of a Plank

Last Set Bit

Last Stone Weight

Last Stone Weight II

Last Substring in Lexicographical Order

Latest Time by Replacing Hidden Digits

Leaf-Similar Trees

Least Common Multiple

Least Interval

Least Number of Unique Integers after K Removals

Least Operators to Express Number

Least Significant Bit

Left and Right Sum Differences

Leftmost Column with at Least a One

Lemonade Change

Length of Longest Fibonacci Subsequence

Length of the Longest Alphabetical Continuous Substring

Length of the Longest Valid Substring

Letter Case Permutation

Letter Combinations

Letter Tile Possibilities

Levels of Indirection

Levels of Indirection and Microfrontend

Leveraging Constraints: A Problem-Solving Strategy from Sudoku to Artificial Intelligence

Lexical Scope in Javascript at Five Levels

Lexical Structure in JavaScript at Five Levels

Lexicographical Numbers

Lexicographically Less Than in Strings

Lexicographically Smallest Beautiful String

Lexicographically Smallest Equivalent String

Lexicographically Smallest Palindrome

Lexicographically Smallest String After Applying Operations

Lexicographically Smallest String After Substring Operation

LFU Cache

License Key Formatting

Lifecycle and Hooks

Line Reflection

Line Sweep

Linear Equation

Linear Inequality

Linear Programming

Linear Scan

Linear Search


Linked List Basics

Linked List Basics Part II

Linked List Components

Linked List Cycle

Linked List Cycle II

Linked List in Binary Tree

Linked List Random Node

List Flattening

List Unflattening

Literal in JavaScript at Five Levels


Log File Analysis

Logarithm at Five Levels

Logger Rate Limiter

Logical Operators in JavaScript

Logical OR of Two Binary Grids Represented as Quad-Trees

Lonely Pixel I

Lonely Pixel II

Long Pressed Name

Longer Contiguous Segments of Ones than Zeros

Longest Absolute File Path

Longest Alternating Subarray

Longest Arithmetic Subsequence

Longest Arithmetic Subsequence of Given Difference

Longest Binary Subsequence Less Than or Equal to K

Longest Chunked Palindrome Decomposition

Longest Common Prefix

Longest Common Subpath

Longest Common Subsequence

Longest Common Subsequence Between Sorted Arrays

Longest Consecutive Sequence

Longest Continuous Increasing Subsequence

Longest Continuous Subarray With Absolute Diff Less Than or Equal to Limit

Longest Cycle in a Graph

Longest Duplicate Substring

Longest Even Odd Subarray With Threshold

Longest Happy Prefix

Longest Happy String

Longest Harmonious Subsequence

Longest Ideal Subsequence

Longest Increasing Path in a Matrix

Longest Increasing Subsequence

Longest Increasing Subsequence II

Longest Line of Consecutive One in Matrix

Longest Mountain in Array

Longest Nice Subarray

Longest Nice Substring

Longest Non-decreasing Subarray From Two Arrays

Longest Palindrome

Longest Palindrome by Concatenating Two Letter Words

Longest Palindromic Subsequence

Longest Palindromic Subsequence II

Longest Palindromic Substring

Longest Path With Different Adjacent Characters

Longest Repeating Character Replacement

Longest Repeating Substring

Longest Simple Cycle Problem

Longest Simple Path in a Directed Acyclic Graph

Longest Square Streak in an Array

Longest String Chain

Longest Subarray of 1's After Deleting One Element

Longest Subarray With Maximum Bitwise AND

Longest Subsequence Repeated k Times

Longest Subsequence With Limited Sum

Longest Substring Of All Vowels in Order

Longest Substring of One Repeating Character

Longest Substring with At Least K Repeating Characters

Longest Substring with At Most K Distinct Characters

Longest Substring with At Most Two Distinct Characters

Longest Substring Without Repeating Characters

Longest Turbulent Subarray

Longest Uncommon Subsequence I

Longest Uncommon Subsequence II

Longest Univalue Path

Longest Uploaded Prefix

Longest Valid Parentheses

Longest Well-Performing Interval

Longest Word in Dictionary

Longest Word in Dictionary through Deleting

Longest Word With All Prefixes

Longest ZigZag Path in a Binary Tree

Loop Invariant

Loud and Rich

Lower Median

Lowest Common Ancestor of a Binary Search Tree

Lowest Common Ancestor of a Binary Tree

Lowest Common Ancestor of a Binary Tree II

Lowest Common Ancestor of a Binary Tree III

Lowest Common Ancestor of a Binary Tree IV

Lowest Common Ancestor of Deepest Leaves

LRU Cache

Lucky Numbers in a Matrix

Machine Learning Explained at Five Levels

Magic Squares In Grid

Magical String

Magnetic Force Between Two Balls

Majority Element

Majority Element II

Make Array Empty

Make Array Non-decreasing or Non-increasing

Make Array Strictly Increasing

Make Array Zero by Subtracting Equal Amounts

Make Costs of Paths Equal in a Binary Tree

Make K-Subarray Sums Equal

Make Number of Distinct Characters Equal

Make String a Subsequence Using Cyclic Increments

Make Sum Divisible by P

Make the Prefix Sum Non-negative

Make The String Great

Make the XOR of All Segments Equal to Zero

Make Two Arrays Equal by Reversing Subarrays

Making A Large Island

Making File Names Unique

Managers with at Least 5 Direct Reports

Map Filter Reduce

Map of Highest Peak

Map Reduce

Map Sum Pairs

Mapping a Problem Model to a Solution Model

Mapping Computer Science Problems to Real-World Scenarios: A Comprehensive Guide

Mark Duplicate Elements by Replacing Them with -1

Masking Personal Information

Mastering Problem-Solving: The Art of Simplification and Reduction in Complex Challenges

Match Substring After Replacement

Matchsticks to Square

Mathematical Expression Evaluation

Mathematical Induction

Mathematical Induction Concept Analysis Diagram

Mathematical Model at Five Levels

Mathematical Modeling

Matrix Block Sum

Matrix Cells in Distance Order

Matrix Diagonal Sum

Matrix-Chain Multiplication

Max Area of Island

Max Chunks To Make Sorted

Max Chunks To Make Sorted II

Max Consecutive Ones

Max Consecutive Ones II

Max Consecutive Ones III

Max Difference You Can Get From Changing an Integer

Max Dot Product of Two Subsequences

Max Increase to Keep City Skyline

Max Number of K-Sum Pairs

Max Pair Sum in an Array

Max Points on a Line

Max Stack

Max Sum of a Pair With Equal Sum of Digits

Max Sum of Rectangle No Larger Than K

Max Value of Equation

Max-Priority Queue

Maximal Network Rank

Maximal Range That Each Element Is Maximum in It

Maximal Rectangle

Maximal Score After Applying K Operations

Maximal Square

Maximize Distance to Closest Person

Maximize Greatness of an Array

Maximize Grid Happiness

Maximize Number of Nice Divisors

Maximize Number of Subsequences in a String

Maximize Palindrome Length From Subsequences

Maximize Score After N Operations

Maximize Sum Of Array After K Negations

Maximize the Beauty of the Garden

Maximize the Confusion of an Exam

Maximize the Minimum Powered City

Maximize the Profit as the Salesman

Maximize the Topmost Element After K Moves

Maximize Total Tastiness of Purchased Fruits

Maximize Win From Two Segments

Maximizing Difference Between Two Ordered Elements

Maximum 69 Number

Maximum Absolute Sum of Any Subarray

Maximum Alternating Subarray Sum

Maximum Alternating Subsequence Sum

Maximum AND Sum of Array

Maximum Area of a Piece of Cake After Horizontal and Vertical Cuts

Maximum Ascending Subarray Sum

Maximum Average Pass Ratio

Maximum Average Subarray I

Maximum Average Subarray II

Maximum Average Subtree

Maximum Bags With Full Capacity of Rocks

Maximum Beauty of an Array After Applying Operation

Maximum Binary String After Change

Maximum Binary Tree

Maximum Binary Tree II

Maximum Building Height

Maximum Candies Allocated to K Children

Maximum Candies You Can Get from Boxes

Maximum Coins Heroes Can Collect

Maximum Compatibility Score Sum

Maximum Consecutive Floors Without Special Floors

Maximum Cost of Trip With K Highways

Maximum Count of Positive Integer and Negative Integer

Maximum Deletions on a String

Maximum Depth of Binary Tree

Maximum Depth of N-ary Tree

Maximum Difference Between Increasing Elements

Maximum Difference Between Node and Ancestor

Maximum Difference by Remapping a Digit

Maximum Distance Between a Pair of Values

Maximum Distance in Arrays

Maximum Earnings From Taxi

Maximum Elegance of a K-Length Subsequence

Maximum Element After Decreasing and Rearranging

Maximum Employees to Be Invited to a Meeting

Maximum Enemy Forts That Can Be Captured

Maximum Equal Frequency

Maximum Erasure Value

Maximum Font to Fit a Sentence in a Screen

Maximum Frequency Score of a Subarray

Maximum Frequency Stack

Maximum Fruits Harvested After at Most K Steps

Maximum Gap

Maximum Genetic Difference Query

Maximum Good People Based on Statements

Maximum Height by Stacking Cuboids

Maximum Ice Cream Bars

Maximum Length of a Concatenated String with Unique Characters

Maximum Length of Pair Chain

Maximum Length of Repeated Subarray

Maximum Length of Subarray With Positive Product

Maximum Level Sum of a Binary Tree

Maximum Matching

Maximum Matching of Players With Trainers

Maximum Matrix Sum

Maximum Nesting Depth of the Parentheses

Maximum Nesting Depth of Two Valid Parentheses Strings

Maximum Non Negative Product in a Matrix

Maximum Number of Accepted Invitations

Maximum Number of Achievable Transfer Requests

Maximum Number of Balloons

Maximum Number of Balls in a Box

Maximum Number of Books You Can Take

Maximum Number of Coins You Can Get

Maximum Number of Consecutive Values You Can Make

Maximum Number of Darts Inside of a Circular Dartboard

Maximum Number of Eaten Apples

Maximum Number of Events That Can Be Attended

Maximum Number of Events That Can Be Attended II

Maximum Number of Fish in a Grid

Maximum Number of Groups Entering a Competition

Maximum Number of Groups Getting Fresh Donuts

Maximum Number of Groups With Increasing Length

Maximum Number of Integers to Choose From a Range I

Maximum Number of Integers to Choose From a Range II

Maximum Number of Jumps to Reach the Last Index

Maximum Number of Moves in a Grid

Maximum Number of Non-overlapping Palindrome Substrings

Maximum Number of Non-Overlapping Subarrays With Sum Equals Target

Maximum Number of Non-Overlapping Substrings

Maximum Number of Occurrences of a Substring

Maximum Number of Ones

Maximum Number of Pairs in Array

Maximum Number of People That Can Be Caught in Tag

Maximum Number of Points From Grid Queries

Maximum Number of Points with Cost

Maximum Number of Removable Characters

Maximum Number of Robots Within Budget

Maximum Number of Tasks You Can Assign

Maximum Number of Visible Points

Maximum Number of Vowels in a Substring of Given Length

Maximum Number of Ways to Partition an Array

Maximum Number of Weeks for Which You Can Work

Maximum Number of Words Found in Sentences

Maximum Number of Words You Can Type

Maximum of Absolute Value Expression

Maximum of Minimum Values in All Subarrays

Maximum OR

Maximum Path Quality of a Graph

Maximum Performance of a Team

Maximum Points in an Archery Competition

Maximum Points with Energy Budget

Maximum Points You Can Obtain from Cards

Maximum Population Year

Maximum Price to Fill a Bag

Maximum Product After K Increments

Maximum Product Difference Between Two Pairs

Maximum Product of Splitted Binary Tree

Maximum Product of the Length of Two Palindromic Subsequences

Maximum Product of the Length of Two Palindromic Substrings

Maximum Product of Three Numbers

Maximum Product of Two Elements in an Array

Maximum Product of Word Lengths

Maximum Product Subarray

Maximum Profit From Trading Stocks

Maximum Profit in Job Scheduling

Maximum Profit of Operating a Centennial Wheel

Maximum Repeating Substring

Maximum Rows Covered by Columns

Maximum Running Time of N Computers

Maximum Score After Splitting a String

Maximum Score from Performing Multiplication Operations

Maximum Score From Removing Stones

Maximum Score From Removing Substrings

Maximum Score of a Good Subarray

Maximum Score of a Node Sequence

Maximum Score Of Spliced Array

Maximum Score Words Formed by Letters

Maximum Segment Sum After Removals

Maximum Side Length of a Square with Sum Less than or Equal to Threshold

Maximum Size Subarray Sum Equals k

Maximum Split of Positive Even Integers

Maximum Star Sum of a Graph

Maximum Strength of a Group

Maximum Strictly Increasing Cells in a Matrix

Maximum Students Taking Exam

Maximum Subarray

Maximum Subarray Min-Product

Maximum Subarray Sum After One Operation

Maximum Subarray Sum with One Deletion

Maximum Subsequence Score

Maximum Sum BST in Binary Tree

Maximum Sum Circular Subarray

Maximum Sum Obtained of Any Permutation

Maximum Sum of 3 Non-Overlapping Subarrays

Maximum Sum of an Hourglass

Maximum Sum of Distinct Subarrays With Length K

Maximum Sum of Two Non-Overlapping Subarrays

Maximum Sum Queries

Maximum Sum Score of Array

Maximum Sum With Exactly K Elements

Maximum Swap

Maximum Tastiness of Candy Basket

Maximum Total Beauty of the Gardens

Maximum Total Importance of Roads

Maximum Trailing Zeros in a Cornered Path

Maximum Twin Sum of a Linked List

Maximum Units on a Truck

Maximum Vacation Days

Maximum Value after Insertion

Maximum Value at a Given Index in a Bounded Array

Maximum Value of a String in an Array

Maximum Value of K Coins From Piles

Maximum White Tiles Covered by a Carpet

Maximum Width of Binary Tree

Maximum Width Ramp

Maximum XOR After Operations

Maximum XOR for Each Query

Maximum XOR of Two Non-Overlapping Subtrees

Maximum XOR of Two Numbers in an Array

Maximum XOR With an Element From Array


Mean of Array After Removing Some Elements


Median at 5 Levels

Median Employee Salary

Median of a Row Wise Sorted Matrix

Median of Two Sorted Arrays

Median-of-3 Method

Meeting Rooms

Meeting Rooms II

Meeting Rooms III

Meeting Scheduler


Mental Model

Mental Model in Programming

Mental Model in React

Merge BSTs to Create Single BST

Merge In Between Linked Lists

Merge Intervals

Merge k Sorted Lists

Merge Nodes in Between Zeros

Merge Operations to Turn Array Into a Palindrome

Merge Similar Items

Merge Sort Variant

Merge Sorted Array

Merge Strings Alternately

Merge Triplets to Form Target Triplet

Merge Two 2D Arrays by Summing Values

Merge Two Binary Trees

Merge Two Sorted Lists


Metacognitive Skills Needed to Solve Algorithmic Problems

Mice and Cheese

Middle of the Linked List

Migrating from Jekyll to Hugo

Mikado Method

Min Amplitude

Min Cost Climbing Stairs

Min Cost to Connect All Points

Min Max Game

Min Stack


Mini Parser

Minimize Deviation in Array

Minimize Hamming Distance After Swap Operations

Minimize Malware Spread

Minimize Malware Spread II

Minimize Max Distance to Gas Station

Minimize Maximum of Array

Minimize Maximum Pair Sum in Array

Minimize Maximum Value in a Grid

Minimize Product Sum of Two Arrays

Minimize Result by Adding Parentheses to Expression

Minimize Rounding Error to Meet Target

Minimize String Length

Minimize the Difference Between Target and Chosen Elements

Minimize the Maximum Difference of Pairs

Minimize the Maximum of Two Arrays

Minimize the Total Price of the Trips

Minimize XOR

Minimized Maximum of Products Distributed to Any Store

Minimum Absolute Difference

Minimum Absolute Difference Between Elements With Constraint

Minimum Absolute Difference in BST

Minimum Absolute Difference Queries

Minimum Absolute Sum Difference

Minimum Add to Make Parentheses Valid

Minimum Addition to Make Integer Beautiful

Minimum Additions to Make Valid String

Minimum Adjacent Swaps for K Consecutive Ones

Minimum Adjacent Swaps to Make a Valid Array

Minimum Adjacent Swaps to Reach the Kth Smallest Number

Minimum Amount of Time to Collect Garbage

Minimum Amount of Time to Fill Cups

Minimum Area Rectangle

Minimum Area Rectangle II

Minimum ASCII Delete Sum for Two Strings

Minimum Average Difference

Minimum Bit Flips to Convert Number

Minimum Changes To Make Alternating Binary String

Minimum Common Value

Minimum Consecutive Cards to Pick Up

Minimum Cost For Tickets

Minimum Cost Homecoming of a Robot in a Grid

Minimum Cost of a Path With Special Roads

Minimum Cost of Buying Candies With Discount

Minimum Cost to Buy Apples

Minimum Cost to Change the Final Value of Expression

Minimum Cost to Connect Sticks

Minimum Cost to Connect Two Groups of Points

Minimum Cost to Cut a Stick

Minimum Cost to Hire K Workers

Minimum Cost to Make All Characters Equal

Minimum Cost to Make Array Equal

Minimum Cost to Make at Least One Valid Path in a Grid

Minimum Cost to Merge Stones

Minimum Cost to Move Chips to The Same Position

Minimum Cost to Reach City With Discounts

Minimum Cost to Reach Destination in Time

Minimum Cost to Separate Sentence Into Rows

Minimum Cost to Split an Array

Minimum Cost Tree From Leaf Values

Minimum Costs Using the Train Line

Minimum Cuts to Divide a Circle

Minimum Degree of a Connected Trio in a Graph

Minimum Deletions to Make Array Beautiful

Minimum Deletions to Make Array Divisible

Minimum Deletions to Make Character Frequencies Unique

Minimum Deletions to Make String Balanced

Minimum Depth of Binary Tree

Minimum Difference Between Highest and Lowest of K Scores

Minimum Difference Between Largest and Smallest Value in Three Moves

Minimum Difference in Sums After Removal of Elements

Minimum Difficulty of a Job Schedule

Minimum Distance Between BST Nodes

Minimum Distance to the Target Element

Minimum Distance to Type a Word Using Two Fingers

Minimum Domino Rotations For Equal Row

Minimum Elements to Add to Form a Given Sum

Minimum Factorization

Minimum Falling Path Sum

Minimum Falling Path Sum II

Minimum Flips in Binary Tree to Get Result

Minimum Flips to Make a OR b Equal to c

Minimum Fuel Cost to Report to the Capital

Minimum Garden Perimeter to Collect Enough Apples

Minimum Genetic Mutation

Minimum Health to Beat Game

Minimum Height Trees

Minimum Hours of Training to Win a Competition

Minimum Impossible OR

Minimum Incompatibility

Minimum Increment to Make Array Unique

Minimum Index of a Valid Split

Minimum Index Sum of Two Lists

Minimum Initial Energy to Finish Tasks

Minimum Insertion Steps to Make a String Palindrome

Minimum Insertions to Balance a Parentheses String

Minimum Interval to Include Each Query

Minimum Jumps to Reach Home

Minimum Knight Moves

Minimum Length of String After Deleting Similar Ends

Minimum Limit of Balls in a Bag

Minimum Lines to Represent a Line Chart

Minimum Money Required Before Transactions

Minimum Moves for Alternating Ball Placement in Buckets

Minimum Moves to Convert String

Minimum Moves to Equal Array Elements

Minimum Moves to Equal Array Elements II

Minimum Moves to Make Array Complementary

Minimum Moves to Move a Box to Their Target Location

Minimum Moves to Reach Target Score

Minimum Moves to Reach Target with Rotations

Minimum Non-Zero Product of the Array Elements

Minimum Number of Arrows to Burst Balloons

Minimum Number of Days to Disconnect Island

Minimum Number of Days to Eat N Oranges

Minimum Number of Days to Make m Bouquets

Minimum Number of Flips to Convert Binary Matrix to Zero Matrix

Minimum Number of Flips to Make the Binary String Alternating

Minimum Number of Food Buckets to Feed the Hamsters

Minimum Number of Frogs Croaking

Minimum Number of Increments on Subarrays to Form a Target Array

Minimum Number of K Consecutive Bit Flips

Minimum Number of Keypresses

Minimum Number of Lines to Cover Points

Minimum Number of Moves to Make Palindrome

Minimum Number of Moves to Seat Everyone

Minimum Number of Operations to Convert Time

Minimum Number of Operations to Make All Array Elements Equal to 1

Minimum Number of Operations to Make Array Continuous

Minimum Number of Operations to Make Arrays Similar

Minimum Number of Operations to Make String Sorted

Minimum Number of Operations to Move All Balls to Each Box

Minimum Number of Operations to Reinitialize a Permutation

Minimum Number of Operations to Sort a Binary Tree by Level

Minimum Number of People to Teach

Minimum Number of Refueling Stops

Minimum Number of Removals to Make Mountain Array

Minimum Number of Steps to Make Two Strings Anagram

Minimum Number of Steps to Make Two Strings Anagram II

Minimum Number of Swaps to Make the Binary String Alternating

Minimum Number of Swaps to Make the String Balanced

Minimum Number of Taps to Open to Water a Garden

Minimum Number of Vertices to Reach All Nodes

Minimum Number of Visited Cells in a Grid

Minimum Number of Work Sessions to Finish the Tasks

Minimum Numbers of Function Calls to Make Target Array

Minimum Obstacle Removal to Reach Corner

Minimum One Bit Operations to Make Integers Zero

Minimum Operations to Convert Number

Minimum Operations to Halve Array Sum

Minimum Operations to Make a Subsequence

Minimum Operations to Make a Uni-Value Grid

Minimum Operations to Make All Array Elements Equal

Minimum Operations to Make Array Equal

Minimum Operations to Make Array Equal II

Minimum Operations to Make Numbers Non-positive

Minimum Operations to Make the Array Alternating

Minimum Operations to Make the Array Increasing

Minimum Operations to Make the Array K-Increasing

Minimum Operations to Reduce an Integer to 0

Minimum Operations to Reduce X to Zero

Minimum Operations to Remove Adjacent Ones in Matrix

Minimum Path Cost in a Grid

Minimum Path Cost in a Hidden Grid

Minimum Path Sum

Minimum Penalty for a Shop

Minimum Possible Integer After at Most K Adjacent Swaps On Digits

Minimum Recolors to Get K Consecutive Black Blocks

Minimum Relative Loss After Buying Chocolates

Minimum Remove to Make Valid Parentheses

Minimum Replacements to Sort the Array

Minimum Reverse Operations

Minimum Rounds to Complete All Tasks

Minimum Score After Removals on a Tree

Minimum Score by Changing Two Elements

Minimum Score of a Path Between Two Cities

Minimum Score Triangulation of Polygon

Minimum Seconds to Equalize a Circular Array

Minimum Sideway Jumps

Minimum Size Subarray Sum

Minimum Skips to Arrive at Meeting On Time

Minimum Space Wasted From Packaging

Minimum Spanning Tree at Five Levels

Minimum Speed to Arrive on Time

Minimum Split Into Subarrays With GCD Greater Than One

Minimum String Length After Removing Substrings

Minimum Subarrays in a Valid Split

Minimum Subsequence in Non-Increasing Order

Minimum Suffix Flips

Minimum Sum of Four Digit Number After Splitting Digits

Minimum Sum of Squared Difference

Minimum Swaps to Arrange a Binary Grid

Minimum Swaps to Group All 1's Together

Minimum Swaps to Group All 1's Together II

Minimum Swaps To Make Sequences Increasing

Minimum Swaps to Make Strings Equal

Minimum Time Difference

Minimum Time For K Virus Variants to Spread

Minimum Time Takes to Reach Destination Without Drowning

Minimum Time to Build Blocks

Minimum Time to Collect All Apples in a Tree

Minimum Time to Complete All Tasks

Minimum Time to Complete Trips

Minimum Time to Eat All Grains

Minimum Time to Finish the Race

Minimum Time to Kill All Monsters

Minimum Time to Make Array Sum At Most x

Minimum Time to Make Rope Colorful

Minimum Time to Remove All Cars Containing Illegal Goods

Minimum Time to Repair Cars

Minimum Time to Type Word Using Special Typewriter

Minimum Time to Visit a Cell In a Grid

Minimum Time Visiting All Points

Minimum Total Cost to Make Arrays Unequal

Minimum Total Distance Traveled

Minimum Total Space Wasted With K Resizing Operations

Minimum Unique Word Abbreviation

Minimum Value to Get Positive Step by Step Sum

Minimum Weighted Subgraph With the Required Paths

Minimum White Tiles After Covering With Carpets

Minimum Window Subsequence

Minimum Window Substring

Minimum XOR Sum of Two Arrays

Mirror Reflection

Mirror Tree

Missing Element

Missing Element in Sorted Array

Missing Number

Missing Number In Arithmetic Progression

Missing Ranges


Model and View in React

Model Categorical Data

Modeling and Simulation

Modeling Quantitative Relationships

Modeling Randomness and Uncertainty

Modeling Relationships and Hierarchies

Modeling Sequential Data

Modify Graph Edge Weights

Modular Arithmetic

Modular Increment

Modular Programming in JavaScript



Modulo Operator

Monitor Background Jobs

Monitor CRON Jobs

Monotone Increasing Digits

Monotonic Array

Monotonic Decreasing Queue

Monotonic Decreasing Stack

Monotonic Stack

Monotonically Decreasing Function

Monotonically Increasing Function

Monte Carlo Method

Most Beautiful Item for Each Query

Most Common Word

Most Frequent Even Element

Most Frequent Number Following Key In an Array

Most Frequent Subtree Sum

Most Popular Video Creator

Most Profit Assigning Work

Most Profitable Path in a Tree

Most Significant Bit

Most Stones Removed with Same Row or Column

Most Visited Sector in a Circular Track

Move Maximum

Move Pieces to Obtain a String

Move Sub-Tree of N-Ary Tree

Move Zeroes

Movement of Robots

Moving Average from Data Stream

Moving Stones Until Consecutive

Moving Stones Until Consecutive II

Multi Key Sort Problem


Multiply Strings


My Calendar I

My Calendar II

My Calendar III

MySQL Deadlock

N-ary Tree Level Order Traversal

N-ary Tree Postorder Traversal

N-ary Tree Preorder Traversal


N-Queens II

N-Repeated Element in Size 2N Array

N-th Tribonacci Number

Naming a Company

Narrowing the Domains of the Variables

Nearest Exit from Entrance in Maze

Neighboring Bitwise XOR

Neither Minimum nor Maximum

Nested Functions in JavaScript

Nested List Weight Sum

Nested List Weight Sum II

Nested Return in React

Network Delay Time

New 21 Game

Next Closest Time

Next Greater Element I

Next Greater Element II

Next Greater Element III

Next Greater Element IV

Next Greater Node In Linked List

Next Greater Numerically Balanced Number

Next Palindrome Using Same Digits

Next Permutation

Nim Game

Node With Highest Edge Score

Non Blocking I/O Model in Javascript at Five Levels

Non Parametric Statistics

Non-decreasing Subsequences

Non-negative Integers without Consecutive Ones

Non-overlapping Intervals

Normal Distribution

Nth Digit

Nth Highest Salary

Nth Magical Number

nth Order Statistic

Number Complement

Number of 1 Bits

Number of Adjacent Elements With the Same Color

Number of Arithmetic Triplets

Number of Atoms

Number of Balanced Subsegments

Number of Beautiful Integers in the Range

Number of Beautiful Pairs

Number of Beautiful Partitions

Number of Black Blocks

Number of Boomerangs

Number of Burgers with No Waste of Ingredients

Number of Closed Islands

Number of Common Factors

Number of Connected Components in an Undirected Graph

Number Of Corner Rectangles

Number of Days Between Two Dates

Number of Days in a Month

Number of Dice Rolls With Target Sum

Number of Different Integers in a String

Number of Different Subsequences GCDs

Number of Digit One

Number of Distinct Averages

Number of Distinct Binary Strings After Applying Operations

Number of Distinct Islands

Number of Distinct Islands II

Number of Distinct Roll Sequences

Number of Distinct Substrings in a String

Number of Employees Who Met the Target

Number of Enclaves

Number of Equal Count Substrings

Number of Equivalent Domino Pairs

Number of Even and Odd Bits

Number of Excellent Pairs

Number of Flowers in Full Bloom

Number of Good Binary Strings

Number of Good Leaf Nodes Pairs

Number of Good Pairs

Number of Good Paths

Number of Good Ways to Split a String

Number of Great Partitions

Number of Increasing Paths in a Grid

Number of Islands

Number of Islands II

Number of Laser Beams in a Bank

Number of Lines To Write String

Number of Longest Increasing Subsequence

Number of Matching Subsequences

Number of Music Playlists

Number of Nodes in the Sub-Tree With the Same Label

Number of Nodes With Value One

Number of Operations to Make Network Connected

Number of Orders in the Backlog

Number of Pairs of Interchangeable Rectangles

Number of Pairs of Strings With Concatenation Equal to Target

Number of Pairs Satisfying Inequality

Number of Paths with Max Score

Number of People Aware of a Secret

Number of People That Can Be Seen in a Grid

Number of Provinces

Number of Recent Calls

Number Of Rectangles That Can Form The Largest Square

Number of Restricted Paths From First to Last Node

Number of Segments in a String

Number of Senior Citizens

Number of Sets of K Non-Overlapping Line Segments

Number of Ships in a Rectangle

Number of Single Divisor Triplets

Number of Smooth Descent Periods of a Stock

Number of Spaces Cleaning Robot Cleaned

Number of Squareful Arrays

Number of Steps to Reduce a Number in Binary Representation to One

Number of Steps to Reduce a Number to Zero

Number of Strings That Appear as Substrings in Word

Number of Students Doing Homework at a Given Time

Number of Students Unable to Eat Lunch

Number of Sub-arrays of Size K and Average Greater than or Equal to Threshold

Number of Sub-arrays With Odd Sum

Number of Subarrays Having Even Product

Number of Subarrays with Bounded Maximum

Number of Subarrays With GCD Equal to K

Number of Subarrays With LCM Equal to K

Number of Submatrices That Sum to Target

Number of Subsequences That Satisfy the Given Sum Condition

Number of Substrings Containing All Three Characters

Number of Substrings With Fixed Ratio

Number of Substrings With Only 1s

Number of Times Binary String Is Prefix-Aligned

Number of Unequal Triplets in Array

Number of Unique Categories

Number of Unique Flavors After Sharing K Candies

Number of Unique Good Subsequences

Number of Valid Clock Times

Number of Valid Move Combinations On Chessboard

Number of Valid Subarrays

Number of Valid Words for Each Puzzle

Number of Valid Words in a Sentence

Number of Visible People in a Queue

Number of Ways of Cutting a Pizza

Number of Ways to Arrive at Destination

Number of Ways to Build House of Cards

Number of Ways to Build Sturdy Brick Wall

Number of Ways to Buy Pens and Pencils

Number of Ways to Divide a Long Corridor

Number of Ways to Earn Points

Number of Ways to Form a Target

Number of Ways to Form a Target String Given a Dictionary

Number of Ways to Paint N × 3 Grid

Number of Ways to Reach a Position After Exactly k Steps

Number of Ways to Rearrange Sticks With K Sticks Visible

Number Of Ways To Reconstruct A Tree

Number of Ways to Reorder Array to Get Same BST

Number of Ways to Select Buildings

Number of Ways to Separate Numbers

Number of Ways to Split a String

Number of Ways to Split Array

Number of Ways to Stay in the Same Place After Some Steps

Number of Ways to Wear Different Hats to Each Other

Number of Ways Where Square of Number Is Equal to Product of Two Numbers

Number of Wonderful Substrings

Number of Zero-Filled Subarrays

Number to Digits

Numbers At Most N Given Digit Set

Numbers With Repeated Digits

Numbers With Same Consecutive Differences

Numerical Stability

Numerically Unstable

Object in JavaScript at Five Levels

Objective Function

Occurrences After Bigram

Odd Even Jump

Odd Even Linked List

Odd Position Elements

Odd String Difference

One Dimensional Array Append

One Dimensional Array Element Delete

One Dimensional Array Element Insert

One Edit Distance

One Way Data Binding in React in 5 Levels

Ones and Zeroes

Online Election

Online Majority Element In Subarray

Online Stock Span

OOP in JavaScript and Ruby

OOP vs Functional Programming

Open the Lock

Operations on Tree

Operators in JavaScript

Optimal Account Balancing

Optimal Binary Search Tree

Optimal Binary Tree

Optimal Division

Optimal Insertion Cost in a Dynamic Sorted Array

Optimal Merge Pattern

Optimal Partition of String

Optimal Substructure and Overlapping Subproblems

Optimization Problems

Optimize Water Distribution in a Village

Order Statistic Tree

Orderly Queue

Orthonormal Vector

Out of Boundary Paths

Output Contest Matches

Pacific Atlantic Water Flow

Package Index

Packer vs Cloud-init

Paint Fence

Paint House

Paint House II

Paint House III

Painting a Grid With Three Different Colors

Painting the Walls

Pairs of Songs With Total Durations Divisible by 60

Pairwise Comparison


Palindrome Linked List

Palindrome Number

Palindrome Pairs

Palindrome Partitioning

Palindrome Partitioning II

Palindrome Partitioning III

Palindrome Partitioning IV

Palindrome Permutation

Palindrome Permutation II

Palindrome Removal

Palindromic Array Transformation

Palindromic Substrings

Palindromic Substrings

Pancake Sorting

Parallel Courses

Parallel Courses II

Parallel Courses III

Parallelism in Computer Science at Five Levels

Pareto Principle

Parse Lisp Expression

Parsing A Boolean Expression

Partition Array According to Given Pivot

Partition Array for Maximum Sum

Partition Array into Disjoint Intervals

Partition Array Into Three Parts With Equal Sum

Partition Array Into Two Arrays to Minimize Sum Difference

Partition Array Such That Maximum Difference Is K

Partition Equal Subset Sum

Partition Function

Partition Labels

Partition List

Partition String Into Minimum Beautiful Substrings

Partition String Into Substrings With Values at Most K

Partition to K Equal Sum Subsets

Partitioning Into Minimum Number Of Deci-Binary Numbers

Partitioning Logic

Partitioning Schemes

Pascal's Triangle

Pascal's Triangle II

Pass the Pillow

Patching Array

Path Compression

Path Crossing

Path In Zigzag Labelled Binary Tree

Path Sum

Path Sum II

Path Sum III

Path Sum IV

Path with Maximum Gold

Path With Maximum Minimum Value

Path with Maximum Probability

Path With Minimum Effort

Path-Relaxation Property

Paths in Matrix Whose Sum Is Divisible by K

Paths in Maze That Lead to Same Room

Patience Sort

Pattern Bias

Peak Index in a Mountain Array

Pecha Kucha

Peeking Iterator

People Whose List of Favorite Companies Is Not a Subset of Another List

Percentage of Letter in String

Perfect Number

Perfect Rectangle

Perfect Squares

Perform String Shifts


Permutation and Combination at Five Levels

Permutation in String

Permutation Sequence


Permutations II

Pig Latin

Pigeonhole Principle

Pizza With 3n Slices

Plates Between Candles

Plus One

Plus One Linked List

Plus Operator in JavaScript

Point of Maximum Overlap

Polya's Problem Solving Technique

Poor Pigs

Pop Count

Populating Next Right Pointers in Each Node

Populating Next Right Pointers in Each Node II

Positions of Large Groups

Possible Bipartition

Pour Water

Pour Water Between Buckets to Make Water Levels Equal

Pow(x, n)

Power Function

Power of Analogy

Power of Four

Power of Heroes

Power of Three

Power of Two

Powerful Integers

Powers of Two

Practice is the Key to Success

Pre Processing


Predict the Winner

Prefix and Suffix Search

Prefix Product

Prefix Substring

Prefix Sum

Preimage Size of Factorial Zeroes Function

Prescriptive Design Method

Previous Permutation With One Swap

Prime Arrangements

Prime In Diagonal

Prime Number of Set Bits in Binary Representation

Prime Pairs With Target Sum

Prime Palindrome

Prime Subtraction Operation

Principle of Intimate Engagement

Print Binary Tree

Print Immutable Linked List in Reverse

Print in a Frame

Print Words Vertically

Priority Queues

Prison Cells After N Days

Probability of a Two Boxes Having The Same Number of Distinct Balls

Probability using MasterChef Competition

Problem Classification

Problem Decomposition

Problem Sequence

Problem Solving Techniques for Coding Interview

Problem Space

Problem Structure Recognition

Problem Transformation

Process Restricted Friend Requests

Process Tasks Using Servers

Product of Array Except Self

Product of the Last K Numbers

Product of Two Run-Length Encoded Arrays

Profitable Schemes

Programming Activities Mapped to Bloom's Taxonomy

Projection Area of 3D Shapes

Promise in Javascript at Five Levels

Proof by Contradiction at Five Levels

Properties in React

Property Checking

Props, Context or HOC?

PropTypes vs Typescript in React

Prototype Chain in JavaScript

Prototype in Javascript at Five Levels

Prune and Search Method

Pruning Function at Five Levels

Pseudo Random Number Generation

Pseudo-Palindromic Paths in a Binary Tree

Public Key Cryptography

Pure Function in Javascript at Five Levels

Push Dominoes

Put Boxes Into the Warehouse I

Put Boxes Into the Warehouse II

Put Marbles in Bags

Pyramid Transition Matrix

Queens That Can Attack the King

Queries on a Permutation With Key

Queries on Number of Points Inside a Circle

Query Batching

Query Kth Smallest Trimmed Number

Queue Basics

Queue Reconstruction by Height



Rabbits in Forest

Race Car

Radix Sort

Radix Tree

Random Flip Matrix

Random Pick Index

Random Pick with Blacklist

Random Pick with Weight

Random Point in Non-overlapping Rectangles

Random Sampling

Range Addition

Range Addition Basics

Range Addition II

Range Caching

Range Check

Range Frequency Queries

Range Module

Range Product

Range Product Queries of Powers

Range Sum

Range Sum of BST

Range Sum of Sorted Subarray Sums

Range Sum Query - Immutable

Range Sum Query - Mutable

Range Sum Query 2D - Immutable

Range Sum Query 2D - Mutable

Rank Scores

Rank Teams by Votes

Rank Transform of a Matrix

Rank Transform of an Array

Ransom Note

Reach a Number


Reachable Nodes In Subdivided Graph

Reachable Nodes With Restrictions

Reaching Points

React at Five Levels

React Component Tag

React State at Five Levels

Read N Characters Given Read4

Read N Characters Given read4 II - Call Multiple Times

Reading React Application Code

Rearrange an Array

Rearrange Array Elements by Sign

Rearrange Array to Maximize Prefix Score

Rearrange Characters to Make Target String

Rearrange Spaces Between Words

Rearrange String k Distance Apart

Rearrange Words in a Sentence

Rearranging Fruits

Recognizing Cues in Problem Statement to Categorize Problem Classes

Reconstruct a 2-Row Binary Matrix

Reconstruct Itinerary

Reconstruct Original Digits from English

Records Created Yesterday in Rails

Recover a Tree From Preorder Traversal

Recover Binary Search Tree

Recover the Original Array

Rectangle Area

Rectangle Area II

Rectangle Overlap

Recurrence Relation

Recursion and Mathematical Induction

Recursion at Five Levels

Recursion Basics

Recursion Tree

Recursive Sum

Redistribute Characters to Make All Strings Equal

Reduce Array Size to The Half


Reducing Dishes

Reduction Algorithm

Reduction Operations to Make the Array Elements Equal

Redundant Connection

Redundant Connection II

Reformat Date

Reformat Phone Number

Reformat The String

Regions Cut By Slashes

Regular Expression Matching

Rejection Sampling

Relationship Analysis in Problem Solving

Relative Ranks

Relative Sort Array

Relocate Marbles

Remove 9

Remove All Adjacent Duplicates In String

Remove All Adjacent Duplicates in String II

Remove All Occurrences of a Substring

Remove All Ones With Row and Column Flips

Remove All Ones With Row and Column Flips II

Remove Boxes

Remove Colored Pieces if Both Neighbors are the Same Color

Remove Comments

Remove Covered Intervals

Remove Digit From Number to Maximize Result

Remove Duplicate Letters

Remove Duplicates

Remove Duplicates From an Unsorted Linked List

Remove Duplicates from Sorted Array

Remove Duplicates from Sorted Array II

Remove Duplicates from Sorted Array II

Remove Duplicates from Sorted List

Remove Duplicates from Sorted List II

Remove Element

Remove in Binary Search Tree

Remove Interval

Remove Invalid Parentheses

Remove K Digits

Remove Letter To Equalize Frequency

Remove Linked List Elements

Remove Max Number of Edges to Keep Graph Fully Traversable

Remove Nodes From Linked List

Remove Nth Node From End of List

Remove One Element to Make the Array Strictly Increasing

Remove Outermost Parentheses

Remove Palindromic Subsequences

Remove Stones to Minimize the Total

Remove Sub-Folders from the Filesystem

Remove Trailing Zeros From a String

Remove Vowels from a String

Remove White Spaces

Remove Zero Sum Consecutive Nodes from Linked List

Removing Minimum and Maximum From Array

Removing Minimum Number of Magic Beans

Removing Stars From a String

Reorder Data in Log Files

Reorder List

Reorder Routes to Make All Paths Lead to the City Zero

Reordered Power of 2

Reorganize String

Repeated DNA Sequences

Repeated String Match

Repeated Substring Pattern

Repeating Elements

Replace All ?'s to Avoid Consecutive Repeating Characters

Replace All Digits with Characters

Replace Elements in an Array

Replace Elements with Greatest Element on Right Side

Replace Non-Coprime Numbers in Array

Replace the Substring for Balanced String

Replace Words

Reservoir Sampling

Reshape the Matrix

Resource Estimation

Restart Sidekiq

Restore IP Addresses

Restore The Array

Restore the Array From Adjacent Pairs

Retrieve Users Based on Timeframe

Reuse in React

Reveal Cards In Increasing Order

Reverse a List

Reverse a Number

Reverse an Array using Auxiliary Array

Reverse Array

Reverse Bits

Reverse Integer

Reverse Linked List

Reverse Nodes in Even Length Groups

Reverse Nodes in k-Group

Reverse Odd Levels of Binary Tree

Reverse Only Letters

Reverse Pairs

Reverse Prefix of Word

Reverse Sentence

Reverse String

Reverse String II

Reverse Subarray To Maximize Array Value

Reverse Substrings Between Each Pair of Parentheses

Reverse Vowels of a String

Reverse Words in a String

Reverse Words in a String II

Reverse Words in a String III

Reward Top K Students

Richest Customer Wealth

Rings and Rods

Rising Temperature

RLE Iterator

Robot Bounded In Circle

Robot Collisions

Robot Return to Origin

Robot Room Cleaner

Rolling Hash

Roman to Integer

Root Equals Sum of Children

Root of the DOM Tree in React

Rotate Array

Rotate Function

Rotate Image

Rotate List

Rotate List

Rotate String

Rotated Digits

Rotating the Box

Rotting Oranges

Row With Maximum Ones

Rule of Product

Run Goss Tests During a Packer Build

Running Average

Running Sum of 1d Array

Russian Doll Envelopes

Sales Person

Same Tree

Satisfiability of Equality Equations

Scope in JavaScript at Five Levels

Score After Flipping Matrix

Score of Parentheses

scp Command

Scramble String

Search a 2D Matrix

Search a 2D Matrix II

Search in a Binary Search Tree

Search in a Sorted Array of Unknown Size

Search in Binary Search Tree

Search in Rotated Sorted Array

Search in Rotated Sorted Array II

Search in Tries

Search Insert Position

Search Minimum

Search Space Reduction

Search Suggestions System

Searching a Log File

Searching the Problem Space

Seat Reservation Manager

Second Largest Digit in a String

Second Minimum Node In a Binary Tree

Second Minimum Time to Reach Destination

Selection Problem

Selection Sort

Self Crossing

Self Dividing Numbers

Sell Diminishing-Valued Colored Balls

Selling Pieces of Wood

Semi-Ordered Permutation

Sender With Largest Word Count

Sentence Screen Fitting

Sentence Similarity

Sentence Similarity II

Sentence Similarity III


Separate the Digits in an Array

Sequence Reconstruction

Sequential Digits

Sequentially Ordinal Rank Tracker

Serialize and Deserialize Binary Tree

Serialize and Deserialize BST

Serialize and Deserialize N-ary Tree

Set Intersection Size At Least Two

Set Matrix Zeroes

Set Mismatch

Set-Partition Problem

Shell Sort

Shift 2D Grid

Shift left, Rotate left in Array

Shifting Letters

Shifting Letters II

Shopping Offers

Short Circuiting Boolean Operators

Short Encoding of Words

Shortest Bridge

Shortest Common Supersequence

Shortest Completing Word

Shortest Cycle in a Graph

Shortest Distance from All Buildings

Shortest Distance to a Character

Shortest Distance to Target Color

Shortest Distance to Target String in a Circular Array

Shortest Impossible Sequence of Rolls

Shortest Palindrome

Shortest Path in a Grid with Obstacles Elimination

Shortest Path in a Hidden Grid

Shortest Path in Binary Matrix

Shortest Path to Get All Keys

Shortest Path to Get Food

Shortest Path Visiting All Nodes

Shortest Path with Alternating Colors

Shortest String That Contains Three Strings

Shortest Subarray to be Removed to Make Array Sorted

Shortest Subarray with Sum at Least K

Shortest Unsorted Continuous Subarray

Shortest Way to Form String

Shortest Word Distance

Shortest Word Distance II

Shortest Word Distance III

Shuffle an Array

Shuffle and Number of Good Pairs

Shuffle String

Shuffle the Array

Sidekiq active (exited)

Sign of the Product of an Array

Similar RGB Color

Similar String Groups

Similarity Mapping Concept Analysis Diagram

Simple Bank System

Simplex Algorithm

Simplified Fractions

Simplify Path

Single Element in a Sorted Array

Single Number

Single Number II

Single Number III

Single or Double Linear Scan

Single Point Structure

Single Purpose Principle

Single-Destination Shortest Path

Single-Pair Shortest-Path Problem

Single-Row Keyboard

Single-Source Shortest Path

Single-Threaded CPU

Skills Needed for Solving a Coding Interview Problem

Skip List

Skip Processing Elements Marked with -1

Sliding Puzzle

Sliding Subarray Beauty

Sliding Window

Sliding Window Maximum

Sliding Window Median

Slowest Key

Smallest Common Region

Smallest Even Multiple

Smallest Good Base

Smallest Greater Multiple Made of Two Digits

Smallest Index With Equal Value

Smallest Integer Divisible by K

Smallest K-Length Subsequence With Occurrences of a Letter

Smallest Missing Genetic Value in Each Subtree

Smallest Missing Non-negative Integer After Operations

Smallest Number in Infinite Set

Smallest Range Covering Elements from K Lists

Smallest Range I

Smallest Range II

Smallest Rectangle Enclosing Black Pixels

Smallest Rotation with Highest Score

Smallest String Starting From Leaf

Smallest String With A Given Numeric Value

Smallest String With Swaps

Smallest Subarrays With Maximum Bitwise OR

Smallest Subsequence of Distinct Characters

Smallest Subtree with all the Deepest Nodes

Smallest Sufficient Team

Smallest Value After Replacing With Sum of Prime Factors

Smallest Value of the Rearranged Number

Snakes and Ladders

Snapshot Array

Solution Space

Solution Structure Recognition

Solve the Equation

Solving Questions With Brainpower

Sort an Array

Sort Array by Increasing Frequency

Sort Array by Moving Items to Empty Space

Sort Array By Parity

Sort Array By Parity II

Sort Characters By Frequency

Sort Colors

Sort Even and Odd Indices Independently

Sort Features by Popularity

Sort Integers by The Number of 1 Bits

Sort Integers by The Power Value

Sort Items by Groups Respecting Dependencies

Sort Linked List Already Sorted Using Absolute Values

Sort List

Sort the Jumbled Numbers

Sort the Matrix Diagonally

Sort the People

Sort the Students by Their Kth Score

Sort Transformed Array

Sort Vowels in a String

Sorting Algorithm Characteristics

Sorting and Searching

Sorting the Sentence

Sorting Three Groups

Soup Servings

Sparse Matrix Multiplication

Special Array With X Elements Greater Than or Equal X

Special Binary String

Special Permutations

Special Positions in a Binary Matrix

Spend Required for Gift Card

Spiral Matrix

Spiral Matrix II

Spiral Matrix III

Spiral Matrix IV

Splay Tree

Split a Circular Linked List

Split a String in Balanced Strings

Split a String Into the Max Number of Unique Substrings

Split Array into Consecutive Subsequences

Split Array into Fibonacci Sequence

Split Array Largest Sum

Split Array with Equal Sum

Split Array With Same Average

Split BST

Split Concatenated Strings

Split Linked List in Parts

Split Message Based on Limit

Split Strings by Separator

Split the Array to Make Coprime Products

Split Two Strings to Make Palindrome

Split With Minimum Sum

Splitting a String Into Descending Consecutive Values

Splitting Sections of HTML

Splitting Summations

Spread Operator in JavaScript

Spread Sheet Decode


Square Root

Squares of a Sorted Array

Squirrel Simulation

Stable Sort

Stack Basics

Stack Depth

Stamping the Grid

Stamping The Sequence

Standard Deviation at Five Levels

State Space Search at Five Levels

Statistics from a Large Sample

Step by Step Guide to Learn React

Step-By-Step Directions From a Binary Tree Node to Another

Stepping Numbers

Steps to Make Array Non-decreasing

Stickers to Spell Word

Stock Price Fluctuation

Stone Game

Stone Game II

Stone Game III

Stone Game IV

Stone Game IX

Stone Game V

Stone Game VI

Stone Game VII

Stone Game VIII

Strange Printer

Strange Printer II

Stream of Characters

Strictly Decreasing Function

Strictly Increasing Function

Strictly Palindromic Number

String Compression

String Compression II

String Matching in an Array

String Segmentation

String to Integer (atoi)

String Transforms Into Another String

String Traversal

String Without AAA or BBB

Strings Differ by One Character

Stripe International Tax setup for Saas

Strobogrammatic Number

Strobogrammatic Number II

Strobogrammatic Number III

Strong Password Checker

Strong Password Checker II

Structure of Code

Structured Problem-Solving Approach

Student Attendance Record I

Student Attendance Record II

Subarray Product Less Than K

Subarray Sum Equals K

Subarray Sums Divisible by K

Subarray With Elements Greater Than Varying Threshold

Subarrays with K Different Integers

Subdomain Visit Count

Subrectangle Queries


Subsequence of Size K With the Largest Even Sum

Subsequence With the Minimum Score

Subset Range


Subsets II

Subsets With Duplicate Characters

Substring with Concatenation of All Words

Substring With Largest Variance

Substring XOR Queries

Substrings of Size Three with Distinct Characters

Substrings That Begin and End With the Same Letter

Subtract the Product and Sum of Digits of an Integer

Subtree of Another Tree

Subtree Removal Game with Fibonacci Tree

Successful Pairs of Spells and Potions

Sudoku Solver

Suffix Product

Suffix Sum

Sum All Elements in a Linked List

Sum Digits

Sum Elements in an Array

Sum Game

Sum in a Matrix

Sum Multiples

Sum of Absolute Differences in a Sorted Array

Sum of All Odd Length Subarrays

Sum of All Subset XOR Totals

Sum of Beauty in the Array

Sum of Beauty of All Substrings

Sum of Digits in Base K

Sum of Digits in the Minimum Number

Sum of Digits of String After Convert

Sum of Distances

Sum of Distances in Tree

Sum of Even Numbers After Queries

Sum of Floored Pairs

Sum of Imbalance Numbers of All Subarrays

Sum of k-Mirror Numbers

Sum of Left Leaves

Sum of Matrix After Queries

Sum of Mutated Array Closest to Target

Sum of Nodes with Even-Valued Grandparent

Sum of Number and Its Reverse

Sum of Numbers With Units Digit K

Sum of Prefix Scores of Strings

Sum of Root To Leaf Binary Numbers

Sum of Scores of Built Strings

Sum Of Special Evenly-Spaced Elements In Array

Sum of Square Numbers

Sum of Squares of Special Elements

Sum of Subarray Minimums

Sum of Subarray Ranges

Sum of Subsequence Widths

Sum of Top K Elements

Sum of Total Strength of Wizards

Sum of Two Integers

Sum of Unique Elements

Sum Root to Leaf Numbers

Summary Ranges

Sums of Squares and Cubes

Super Egg Drop

Super Palindromes

Super Pow

Super Ugly Number

Super Washing Machines

Surface Area of 3D Shapes

Surrounded Regions

Swap Adjacent in LR String

Swap For Longest Repeated Character Substring

Swap Nodes in Pairs

Swapping Nodes in a Linked List

Swim in Rising Water

Symbol in JavaScript at Five Levels

Symmetric Tree

Symmetry and Invariance in Problem Solving

Synonymous Sentences

System Model

System Package

Table of Contents

Tag Validator

Tail Recursion at Five Levels

Take Gifts From the Richest Pile

Take K of Each Character From Left and Right

Tallest Billboard

Target Sum

Task Scheduler

Task Scheduler II

Taylor Expansion

Taylor Series

Teemo Attacking

Telescoping Series

Ternary Expression Parser

Text Justification

The Art of Problem-Solving Through Analogical Reasoning

The Earliest and Latest Rounds Where Players Compete

The Earliest Moment When Everyone Become Friends

The Employee That Worked on the Longest Task

The First Step to Effective Problem-Solving

The Greedy Method

The k Strongest Values in an Array

The K Weakest Rows in a Matrix

The k-th Lexicographical String of All Happy Strings of Length n

The Knight’s Tour

The kth Factor of n

The Latest Time to Catch a Bus

The Maze

The Maze II

The Maze III

The Most Similar Path in a Graph

The Number of Beautiful Subsets

The Number of Full Rounds You Have Played

The Number of Good Subsets

The Number of the Smallest Unoccupied Chair

The Number of Weak Characters in the Game

The Pitfalls of Over-Reliance on Code Blueprints

The Score of Students Solving Math Expression

The Skyline Problem

The this keyword in Javascript at Five Levels

The Time When the Network Becomes Idle

Theory at Five Levels

Think Like Alan Turing

Think Like Claude Shannon

Think Like Dijkstra to Solve Problems

Think Like Donald Knuth

Think Like Grace Hopper

Think Like John von Neumann

Think Like Richard Bellman

Think Like Richard Feynman

Think Like Soborno Bari the Child Prodigy

Think Like Socrates to Become a Genius

Think with Pen and Paper

Thinking and Reasoning

Thinking Process for DP Problems

Third Maximum Number

Thought Experiment

Thousand Separator

Thread in JavaScript at Five Levels

Three Consecutive Odds

Three Divisors

Three Equal Parts

Three Pointers

Throne Inheritance

Tiling a Rectangle with the Fewest Squares

Time Based Key-Value Store

Time Needed to Buy Tickets

Time Needed to Inform All Employees

Time Needed to Rearrange a Binary String

Time Taken to Cross the Door

Time to Cross a Bridge

To Lower Case

Toeplitz Matrix

Too many connections error in MySQL

Top K Frequent Elements

Top K Frequent Words

Top Level in JavaScript

Topological Sort

Toss Strange Coins

Total Appeal of A String

Total Cost to Hire K Workers

Total Distance Traveled

Total Hamming Distance

Traceability in React

Transform and Conquer: Solving Computational Problems through Problem Reduction

Transform to Chessboard

Transitioning from Visual Model to Code

Transitive Closure

Transitive Closure of a Directed Graph

Transitive Relationship at Five Levels

Translating Manual Process

Transpose Matrix

Trapping Rain Water

Trapping Rain Water II

Traverse Forward and Backward

Traversing Two Trees in Parallel


Tree Diameter

Tree Node

Tree of Coprimes

Tree Size

Tree Traversal




Trim a Binary Search Tree

Triples with Bitwise AND Equal To Zero


Trips and Users

Truncate Sentence

Tuple with Same Product

Tweet Counts Per Frequency

Two Best Non-Overlapping Events

Two City Scheduling

Two Furthest Houses With Different Colors

Two Out of Three

Two Pass Method

Two Pointers

Two Sum

Two Sum BSTs

Two Sum II - Input Array Is Sorted

Two Sum III - Data structure design

Two Sum IV - Input is a BST

Two Sum Less Than K

Two Sum Series

Two Sum Variations

Ugly Number

Ugly Number II

Ugly Number III

Ukkonen's Algorithm

Uncommon Words from Two Sentences

Uncrossed Lines

Understanding Function References and Lazy Evaluation in React

Understanding JavaScript's Single-Threaded Execution and the Role of Web Workers

Understanding React: A Library and a Rendering Framework

Understanding Stepwise Refinement: A Layered Approach from Child to Expert

Understanding the Greedy Approach: Can Kids Have Maximum Candies?

Unicode in Five Levels

Unidirectional Data Flow in React

Uniform Distribution

Union by Rank

Unique Binary Search Trees

Unique Binary Search Trees II

Unique Characters

Unique Email Addresses

Unique Length-3 Palindromic Subsequences

Unique Morse Code Words

Unique Number of Occurrences

Unique Paths

Unique Paths II

Unique Paths III

Unique Substrings in Wraparound String

Unique Substrings With Equal Digit Frequency

Unique Word Abbreviation

Univalued Binary Tree

Unrolling the Recursion

Unveiling the Power of Visualization in Problem-Solving

Upgrading Django

Upgrading Rails

Upper Median

useEffect in React

Using a Robot to Print the Lexicographically Smallest String

Using Constraints to Solve Algorithmic Problems

Using Logstash with Rails

Using Model to Solve Problem

Using Programming to Learn Programming

UTF at Five Levels

UTF-8 Validation

Valid Anagram

Valid Arrangement of Pairs

Valid Boomerang

Valid Mountain Array

Valid Number

Valid Palindrome

Valid Palindrome II

Valid Palindrome III

Valid Palindrome IV

Valid Parentheses

Valid Parenthesis String

Valid Perfect Square

Valid Permutations for DI Sequence

Valid Square

Valid Sudoku

Valid Tic-Tac-Toe State

Valid Triangle Number

Valid Word Abbreviation

Valid Word Square

Validate Binary Search Tree

Validate Binary Tree Nodes

Validate IP Address

Validate Stack Sequences

Variable in JavaScript at Five Levels


Variational Method of Problem Solving

Verbal Arithmetic Puzzle

Verification of Spanning Trees

Verify Preorder Sequence in Binary Search Tree

Verify Preorder Serialization of a Binary Tree

Verifying an Alien Dictionary

Vertex Articulation Point

Vertex Cover Problem

Vertex Set

Vertical Order Traversal of a Binary Tree

Video Stitching

Visit Array Positions to Maximize Score

Visual Model of a Problem

Visual Model of the Problem

Visualization: The Key to Understanding and Solving Complex Problems

Visualizing Backtracking

Vowel Spellchecker

Vowels of All Substrings

Walk of a Tree

Walking Robot Simulation

Walking Robot Simulation II

Walls and Gates

Warehouse Packer's Dilemma

Water and Jug Problem

Water Bottles

Watering Plants

Watering Plants II

Ways to Express an Integer as Sum of Powers

Ways to Invoke Functions in JavaScript

Ways to Make a Fair Array

Ways to Split Array Into Good Subarrays

Ways to Split Array Into Three Subarrays

Ways to Split String

Weak Duality

Web Crawler

Weight Function for a Graph

Weight Function in a Weighted Matroid

Weight-Balanced Tree

Weighted Bipartite Matching

Weighted Lower Median

Weighted Matroid

Weighted Median

Weighted Set-Covering Problem

Weighted Vertex Cover

Weighted Vertex Cover Problem

Weighted-Union Heuristic

What is Component in React?

Where Will the Ball Fall

White Vertex

White-Path Theorem

Widest Pair of Indices With Equal Range Sum

Widest Vertical Area Between Two Points Containing No Points

Wiggle Sort

Wiggle Sort II

Wiggle Subsequence

Wildcard Matching

Winning Candidate

Wishful Thinking and Make it Easier

Word Abbreviation

Word Break

Word Break II

Word Ladder

Word Ladder II

Word Pattern

Word Pattern II

Word Search

Word Search II

Word Squares

Word Subsets

Words Within Two Edits of Dictionary

Work-Stealing Scheduling Algorithm

Working Backwards at Five Levels

X of a Kind in a Deck of Cards

XOR Operation in an Array

XOR Queries of a Subarray

Young Tableaus

ZigZag Conversion

Zigzag Iterator

Zuma Game