LongestPalindrome.java

public class LongestPalindrome {

    public String longestPalindrome(String s) {

        int length = s.length() - 1;
        if(length <= 0) return s;

        char[] input = s.toCharArray();

        String palindrome = String.valueOf(s.charAt(0));
        for(int i = 0; i<=length; i++){
            for(int j = length; j>i; j--) {
                if (input[i] != input[j]) continue;
                for (int k = j, puntTemp = i; k >= i; k--, puntTemp++) {
                    if(k == i){
                        if(s.substring(i,j).length()>=palindrome.length()){
                            palindrome = s.substring(i,j+1);
                            if(palindrome.length() >= length-i) return palindrome;
                        }
                    }
                    if (input[puntTemp] != input[k]) break;
                }
            }
        }
        return palindrome;
    }
}