public class Ex17 {
    public static void main(String[] args) {

        String word = "abcabcXyyzzf";

        char[] singleChar = new char[word.length()];
        String[] checkArray = new String[word.length()];

        for (int i = 0; i < singleChar.length; i++) {
            singleChar[i] = word.charAt(i);
            for (int j = 0; j < singleChar.length; j++) {
                singleChar[j] = word.charAt(j);
                if (singleChar[i] == singleChar[j] && i != j) {
                    checkArray[i] = "repeated";
                }
            }

            if (checkArray[i] != "repeated") {
                System.out.println("First non-repeating character in word - " + word + " - is " + singleChar[i] + " at index: " + i);
                break;
            }
        }
    }
}