import java.util.Arrays;

public class Main {
    private static void permutation(int[] seed) {
        int[] perm = new int[seed.length];
        boolean[] used = new boolean[seed.length];
        buildPerm(seed, perm, used, 0);
    }

    private static void buildPerm(int[] seed, int[] perm, boolean[] used, int index) {
        if (index == seed.length) {
            procPerm(perm);
            return;
        }

        for (int i = 0; i < seed.length; ++i) {
            if (used[i]) continue;
            perm[index] = seed[i];
            used[i] = true;
            buildPerm(seed, perm, used, index + 1);
            used[i] = false;
        }
    }

    private static void procPerm(int[] perm) {
        // Use the perm[] here.
        System.out.println(Arrays.toString(perm));
    }

    public static void main(String[] args) {
        permutation(new int[]{1, 2, 3});
    }
}