package leetcode;

public class Huiwenchuan {

    private String longestPalindrome(String str){
        int length = str.length();
        char[] charArray = str.toCharArray();
        boolean[][] dp = new boolean[length][length];
        for(int i = 0; i<length; i++){
            dp[i][i] = true;
        }

        int begin = 0;
        int max = 1;
        for(int i = 0; i<length; i++){
            for(int j=0; j<i; j++){
                if(charArray[i] != charArray[j]){
                    dp[i][j] = false;
                } else {
                    if(i-1-(j+1)<2){
                        dp[i][j] = true;
                    } else {
                        dp[i][j] = dp[i-1][j+1];
                    }
                }

                if(dp[i][j] && i-j+1>max){
                    begin = j;
                    max = i-j+1;
                }
            }
        }
        return str.substring(begin, begin+max);
    }

    public static void main(String[] args) {
        Huiwenchuan huiwenchuan = new Huiwenchuan();
        System.out.println(huiwenchuan.longestPalindrome("abacab"));
    }
}