#include<stdio.h>
#include<algorithm>
#include<string.h>
using namespace std;
int n,m;
int temp=100;
int v[100];
int a[30];
void dfs(int deep,int t)
{
    //printf("%d-\n",deep);
    if(t==0)
    {
        //printf("-%d\n",t);
        //printf("%d\n",deep);
        temp=min(temp,deep);
        return ;
    }
        for(int i=n-1;i>=0;i--)
        {
            if(v[i]==0&&t>=a[i])
            {
                v[i]=1;
                dfs(deep+1,t%a[i]);
                v[i]=0;
            }
        }
}
int main()
{
    int t;
    while(scanf("%d",&t)!=-1)
    {
        while(t--)
        {
            scanf("%d%d",&n,&m);

            for(int i=0;i<n;i++)
            scanf("%d",&a[i]);
            sort(a,a+n);
            temp=100;
            memset(v,0,sizeof(v));
            dfs(0,m);
            if(temp==100)
                puts("-1");
            else
                printf("%d\n",temp);
        }
    }
}