114. Longest Repeating Character Replacement

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Example 1:

Input: s = "ABAB", k = 2

Output: 4

Explanation: We can replace the two 'A's with 'B's or vice versa to obtain "BBBB" or "AAAA" of length 4.

Example 2:

Input: s = "AABABBA", k = 1

Output: 4

Explanation: Replace the one 'A' in the middle with a 'B' to obtain "AABBBBA" then the longest substring of repeating characters is "BBBB" with the length of 4.

Example 3:

Input: s = "AAAA", k = 0

Output: 4

Explanation: No replacements are needed, so the longest substring is the entire string "AAAA" with length 4.

Constraints:

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Time Complexity

O(n)

Space Complexity

O(1)

114. Longest Repeating Character Replacement

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