public class ComparingStrings {
    public static String compare(String s1, String s2) {
        String str = "";
        char letter;
       for (int i = 0; i < s2.length(); i++) {
           letter = s2.charAt(i);
           for (int j = 0; j < s1.length(); j++) {
               if (s1.charAt(j) == (letter)) {
                   str = str + letter;
                   break;
               }
           }
       } return str;
    }

    public static void main(String[] args) {
        String s1, s2, str;
        s1 = "AGGTAB";
        s2 = "GXTXAYB";
       str = ComparingStrings.compare(s1, s2);
        System.out.println("Equal Elements: " + str);
    } // End Main
} // End Class