Variations

import java.util.ArrayList;
import java.util.Scanner;

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

        Scanner scanner = new Scanner(System.in);
        //        On the first line, find the number Z
        int length = scanner.nextInt();
        scanner.nextLine();
//        On the second line, find the symbols X and Y
        String[] input = scanner.nextLine().split(" ");
        String symb1 = input[0];
        String symb2 = input[1];
        String symbols = symb1 + symb2;

        String result = "";
//        Print one variation on each line
//        Ordered lexicographically
//        Print to the standard output
          combine(result, symbols, length);
    }

    private static void combine(String result, String input, int length) {
        if (length == 0) {
            System.out.println(result);  // base condition
        } else {
//            for (Character character: input.toCharArray()) {
//                combine(result + character, input, length - 1);
//            }
            for (int i = input.length() - 1; i >= 0; i--) {
                combine(result + input.charAt(i), input, length - 1);
            }

        }
    }
}