public static String longestPalindrome(String s) {

if (s == null || s.length() < 1) return "";

int start = 0, end = 0;

for (int i = 0; i < s.length(); i++) {

int left = i, right = i;

while (left >= 0 && right < s.length() && s.charAt(left) == s.charAt(right)) {

if (right - left >= end - start) { // Check if longest pal

start = left;

end = right;

}

left --;

right ++;

}

// Even-length pali

left = i;

right = i + 1;

while (left >= 0 && right < s.length() && s.charAt(left) == s.charAt(right)) {

if (right - left >= end - start) {

start = left;

end = right;

}

left --;

right ++;

}

}

return s.substring(start, end + 1);

}

public static void main(String[] args) {

String s1 = "abcdefedc";

System.out.println(longestPalindrome(s1));

System.out.println();

String s2 = "abrbadaadab";

System.out.println(longestPalindrome(s2));

}