搜索题目,题意:给定n和a,然后一个序列b1……bn,问能不能从序列中取出任意个数组成c1……cn,然后满足a mod c1 mod c2……mod cn = 0;
#include <stdio.h>
#include <string.h>
#include <algorithm>
using namespace std;
#pragma warning (disable :4996)
const int N = 22;
int a[N], m, n, ans;
bool Vis[N];
void DFS(int num, int cnt)
{
if (num == n)
{
int tem = m;
for (int i = n - 1; i >= 0; i--)
{
if (Vis[i])
{
tem %= a[i];
}
if (!tem)
{
ans = min(ans, cnt);
}
}
return;
}
Vis[num] = 0;
DFS(num + 1, cnt);
Vis[num] = 1;
DFS(num + 1, cnt + 1);
}
int main()
{
int T;
scanf("%d", &T);
while (T--)
{
memset(Vis, 0, sizeof(Vis));
scanf("%d %d", &n, &m);
for (int i = 0; i < n; i++)
scanf("%d", &a[i]);
sort(a, a + n);
ans = 1 << 29;
DFS(0, 0);
if (ans == 1 << 29)
puts("-1");
else printf("%d\n", ans);
}
return 0;
}
a mod c1 mod c2 mod… mod cr=0