[LeetCode] Longest Substring with At Least K Repeating Characters 至少有K个重复字符的最长子字符串

Find the length of the longest substring T of a given string (consists of lowercase letters only) such that every character in T appears no less than k times.

Example 1:

Input:
s = "aaabb", k = 3

Output:
3

The longest substring is "aaa", as ‘a‘ is repeated 3 times.

Example 2:

Input:
s = "ababbc", k = 2

Output:
5

The longest substring is "ababb", as ‘a‘ is repeated 2 times and ‘b‘ is repeated 3 times.

s

[LeetCode] Longest Substring with At Least K Repeating Characters 至少有K个重复字符的最长子字符串

原文：http://www.cnblogs.com/grandyang/p/5852352.html