uva - 729 - The Hamming Distance Problem

#define Local
#include <iostream>
#include <iomanip>
#include <string>
#include <cstring>
#include <cstdio>
#include <queue>
#include <stack>
#include <algorithm>
#include <cmath>

using namespace std;
#define MAX 20
int H, N;
void print_binary (int n)
{
	int i = 0;
	int bin[MAX];
	memset(bin, 0, sizeof(bin));
	while(n)
	{
		bin[i++] = n % 2;
		n /= 2;
	}
	for (i = H-1; i >= 0; i--)
		cout << bin[i];
	cout << endl;
}
int main()
{
#ifdef Local
	freopen("a.in", "r", stdin);
	freopen("a.out", "w", stdout);
#endif
	int t = 0, max = 0, i = 0, j = 0;
	cin >> t;
	while (t--)
	{
		cin >> H >> N;
		max = pow(2, H)-1;
		for (i = 0; i <= max; i++)
		{
			int temp = i, num = 0;
			while (temp)
			{
				temp &= (temp-1);
				num++;
			}
			if (N == num)
			{
				print_binary(i);
			}
		}
		if (t)
			cout << endl;
	}
}