Sum of Unique Elements
We can create a dictionary to count the frequency of each element in the list. Once we have the frequency count, we can iterate over the dictionary to sum up the unique elements (those with a count of 1).
Here’s the Python code for this:


This approach works by first building a frequency dictionary count
for all numbers in nums
. It then goes through the dictionary and sums up all the numbers which have a frequency of 1 (i.e., unique numbers). The sum is then returned.
Single Loop

