Remove Digit From Number to Maximize Result

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class Solution:
    def removeDigit(self, number: str, digit: str) -> str:
        arr = []

        for index in range(len(number)):
            if number[index] == digit:
                removed_digit_number = number[0:index] + number[index+1:]
                arr.append(int(removed_digit_number))

        max_value = max(arr)
        return str(max_value)

This code is doing the following:

1. Creating an empty list, arr.
2. Looping through the indices of number. If the current digit is equal to digit, it removes this digit from number and appends the resulting number to arr.
3. Finding the maximum value in arr.
4. Converting this maximum value to a string and returning it.

Q&A

what is the mistake in my solution

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class Solution:
def removeDigit(self, number: str, digit: str) -> str:
arr=[]
number=input()
digit=input()
for _ in range(len(number)):
if number[]==digit:
arr.append(int(number[0::1]+number[_+1::]))
max(arr)

Your solution seems to have a few errors and misunderstandings:

1. number=input() and digit=input(): These lines are unnecessary. The function’s arguments number and digit are already being passed in when the function is called. You should remove these lines.

2. if number[]==digit:: This line has a syntax error. It seems like you want to iterate over the digits in number, but you forgot to include the index inside the brackets.

3. arr.append(int(number[0::1]+number[_+1::])): This line will append the integer version of the string number without the current digit to arr. However, your slicing seems to be off. number[0::1] will include all the digits in number, and number[_+1::] will include all digits after the current one. This would not exclude the current digit from the result.

4. max(arr): This line returns the maximum value in arr, but it does not convert it back to a string. Also, it’s not inside a return statement, so the function does not return anything.

A corrected version of your function could look like this:

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class Solution:
    def removeDigit(self, number: str, digit: str) -> str:
        arr = []
        for _ in range(len(number)):
            if number[_] == digit:
                arr.append(int(number[0:_] + number[_+1:]))
        return str(max(arr))

This version of your function removes the digit from number at every possible position and stores the resulting numbers in arr. Then it finds the maximum value in arr, converts it to a string and returns it. However, this is not the correct approach to the problem because you’re not seeking to create the maximum number by removing a digit at every possible position but to create the maximum number by removing a digit once. For this reason, you need to follow a different approach like the one provided in the previous response.