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package infoboard;

import java.util.ArrayList;
import java.util.Arrays;

public class Main {

	public static void main(String[] args) {
		ArrayList<int[]> tmp = new ArrayList<int[]>();
		comb(new int[] { 1, 2, 3 }, new int[11], 0, tmp);
		for (int[] permut : tmp) {
			System.out.println(Arrays.toString(permut));
		}
	}

	static void comb(int[] alphabet, int[] taken, int index, ArrayList<int[]> result) {
		if (index == taken.length) {
			result.add(Arrays.copyOf(taken, taken.length));
			return;
		}
		for (int next : alphabet) {
			taken[index] = next;
			comb(alphabet, taken, index + 1, result);
		}
	}
}

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static int[][] comb(int[] alphabet, int take) {
	int count = (int) Math.pow(alphabet.length, take);
	int[][] result = new int[count][];
	for (int i = 0; i < count; i++) {
		result[i] = new int[take];
		int n = i;
		for (int j = take - 1; j >= 0; j--) {
			result[i][j] = alphabet[n % alphabet.length];
			n /= alphabet.length;
		}
	}
	return result;
}