LeetCode #: 1208
Difficulty: Medium
Topics: Array, sliding window.
First, we need to understand that this problem deals with the differences between the characters in s and t, rather than the actual characters.
To get the maximum length of substring with a cost less than or equal to maxCost, we use the sliding window technique on the differences to get the maximum length.
Assume n is the number of characters in s.
Time complexity: O(n)
Space complexity: O(1)