Longest Repeating Character Replacement

You are given a string s and an integer k. Your task is to determine the length of the longest substring you can obtain from s by replacing at most k characters so that all the characters in the substring are the same.

For a substring of length L with a most frequent character count of maxCount, the condition for it to be valid after at most k replacements is:

\(L - \text{maxCount} \le k\)

If the condition is violated, you need to shrink the window. This problem can be efficiently solved using a sliding window approach.

inputFormat

The input is given via stdin in two lines:

• The first line contains the string s.
• The second line contains the integer k, representing the maximum number of allowed character replacements.

outputFormat

Output a single integer representing the length of the longest substring that can be obtained after at most k replacements, printed to stdout.

AABABBA
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