字符串系列一＞最长回文子串

题目：

链接: link

解析：

代码：

class Solution {public String longestPalindrome(String s) {char[] ss = s.toCharArray();int n = ss.length;int begin = 0;//返回结果的起始字符串int len = 0;//判断返回的字符串是否为最长的字符串for(int i = 0; i < n; i++){//先扩展偶数int left = i, right = i;while(right < n && left >= 0 && ss[left] == ss[right]){left--;right++;}if(right-left-1 > len){len = right-left-1;begin = left+1;}//扩展偶数left = i;right = left+1;while(right < n && left >= 0 && ss[left] == ss[right]){left--;right++;}if(right-left-1 > len){len = right-left-1;begin = left+1;}}return s.substring(begin,begin + len);}
}