longestPalindromicSubstring.md

## 题目描述
Given a string s, find the longest palindromic substring in s. You may assume that the maximum length of s is 1000.

Example:
```
Input: "babad"

Output: "bab"
```
> Note: "aba" is also a valid answer.


Example:
```
Input: "cbbd"

Output: "bb"
 ```
## 思路

## 代码
```js
/**
 * @param {string} s
 * @return {string}
 */
var longestPalindrome = function(s) {
    
};
```