Solution: Longest Repeating Character Replacement

Statement

Given a string, s, and an integer, k, find the length of the longest substring in s, where all characters are identical, after replacing, at most, k characters with any other uppercase English character.

Constraints:

• $1 \leq$ s.length $\leq 10^3$

• s consists of only uppercase English characters.

• $0 \leq$ ...