标签：aabb 思路 least ++ bsp cto class repeat cte
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.
解题思路：每次找到字符串中不符合条件的字符，然后把它分成两部分。
class Solution { public: int helper(const string &s, int start, int end, int k) { if(end - start < 1) return 0; vector<int>hash(26, 0); for(int i = start; i < end; i++) { hash[s[i]-‘a‘]++; } for(int i = 0; i < 26; i++) { if(hash[i] && hash[i] < k ) { for(int j = start; j < end; j++){ if(s[j] == i + ‘a‘) { return max(helper(s, start, j, k), helper(s, j+1, end, k)); } } } } return end - start; } int longestSubstring(string s, int k) { return helper(s, 0, s.length(), k); } };
395. Longest Substring with At Least K Repeating Characters
标签：aabb 思路 least ++ bsp cto class repeat cte
原文地址：http://www.cnblogs.com/tsunami-lj/p/7681070.html
