public class Main {
    public static boolean isPalindrome(String s) {
        return s.length() < 2 || (s.charAt(0) == s.charAt(s.length() - 1)
            && isPalindrome(s.substring(1, s.length() - 1)));
    }

    public static void main(String[] args) {
        System.out.println(isPalindrome("Kaak"));
    }
}