[Leetcode]5. Longest Palindromic Substring

5. Longest Palindromic Substring

Given a string s, find the longest palindromic substring in s. You may assume that the maximum length of s is 1000.
Example 1:

Input: "babad"
Output: "bab"
Note: "aba" is also a valid answer.
Example 2:

Input: "cbbd"
Output: "bb"
题意：求字符串中最长回文子串

class Solution {
public:
    string longestPalindrome(string s) {
        string res;
        for(int i=0;i=0&&k=0&&k