package com.liang.leetcode;
/**
* @ClassName L5
* @description longest-palindromic-substring
* @Author LiaNg
* @Date 2018/12/6
*/
public class L5 {
public static void main(String[] args) {
String str = "bababd";
L5 l = new L5();
System.out.println(l.longestPalindrome(str));
}
/**
* 给定一个字符串 s，找到 s 中最长的回文子串。你可以假设 s 的最大长度为 1000。
*/
private String longestPalindrome(String s) {
int n = s.length();
if (n <= 1) {
return s;
}
String longest = "";
String str;
for (int i = 0; i < n - 1; i++) {
str = findPalindrome(s, i, i);
if (str.length() > longest.length()) {
longest = str;
}
str = findPalindrome(s, i, i + 1);
if (str.length() > longest.length()) {
longest = str;
}
}
return longest;
}
private String findPalindrome(String str, int left, int right) {
int n = str.length();
int l = left;
int r = right;
while (l >= 0 && r <= n - 1 && str.charAt(l) == str.charAt(r)) {
l--;
r++;
}
return str.substring(l + 1, r);
}
}