位向量法生成子集

import java.util.Scanner;

public class 位向量法 {

	public static int[] a = new int[10];

	public static void print_subSet(int n, int cur) {
		if (cur == n) {
			for (int i = 0; i < cur; i++) {
				if (a[i] == 1)
					System.out.print((i + 1));
			}
			System.out.println();
			return;
		}
		a[cur] = 1;
		print_subSet(n, cur + 1);
		a[cur] = 0;
		print_subSet(n, cur + 1);
	}

	public static void main(String[] args) {
		Scanner s = new Scanner(System.in);
		int n = s.nextInt();
		print_subSet(n, 0);
	}

}