摘要：https://leetcode.com/problems/longest-palindromic-substring/ 题目： Given a string S, find the longest palindromic substring in S. You may assume that th 阅读全文

摘要：https://leetcode.com/problems/implement-strstr/ 题目： Implement strStr(). Returns the index of the first occurrence of needle in haystack, or -1 if need 阅读全文