抽签问题（枚举）

#include<iostream>
using namespace std;

int main()
{
	int n, m, q[55], flag = 0;

	cin >> n;
	for (int i = 0; i < n; i++) cin >> q[i];
	cin >> m;

	// 核心操作：枚举
	for (int a = 0; a < n;a++)
	for (int b = 0; b < n;b++)
	for (int c = 0; c < n;c++)
	for (int d = 0; d < n;d++)
	if (q[a] + q[b] + q[c] + q[d] == m)
		flag = 1;
	
	if (flag) cout << "Yes" << endl;
	else cout << "No" << endl;
	return 0;
}