K-Character Anagram Substring

Given a string `s` and an integer `k`, determine if there exists any substring of length `k` which is an anagram of another substring of the same length. Input: - The first line contains an integer n (1 ≤ n ≤ 10^5), the length of the string. - The second line contains the string `s`, consisting of lowercase English letters. - The third line contains an integer k (1 ≤ k ≤ n). Output: - Print 'True' if at least one anagrammatic substring of length `k` exists; otherwise print 'False'. Example: Input: 8 ababaaba 3 Output: True