Max Length of Equal Substrings

You are given a string 's' consisting of only 'a' and 'b'. You can modify at most 'k' characters from 'a' to 'b' or from 'b' to 'a'. Find the length of the longest substring containing all 'a' or all 'b' after performing at most 'k' modifications. Input Format: - The first line contains the string 's' (1 ≤ |s| ≤ 10^5). - The second line contains an integer 'k' (0 ≤ k ≤ |s|). Output Format: - Print a single integer representing the maximum length of the substring that can be achieved. Example: Input: aabbaaa 1 Output: 5 (The longest substring is 'aaaaa' which can be formed by changing one 'b' to 'a'.)