#include <cstdio>
#include <cstring>
#include <cstdlib>
#include <string>
#include <iostream>
#include <algorithm>
#include <sstream>
#include <cmath>
using namespace std;
#include <queue>
#include <stack>
#include <vector>
#include <deque>
#include <bitset>
#include <set>
#include <map>
#pragma comment(linker, "/STACK:1024000000,1024000000")
#define clc(arr, val)    memset(arr, val, sizeof(arr))
#define FOR(i,a,b)  for(int i=a;i<=b;i++)
#define IN   freopen ("in.txt" , "r" , stdin);
#define OUT  freopen ("out.txt" , "w" , stdout);
typedef long long  LL;
typedef unsigned long long  ULL;
const int MAXN = 120000;
const int MAXM = 6000010;
const int INF = 0x3f3f3f3f;
const LL mod = (LL)1<<32;
const double eps= 1e-8;
const double pi=acos(-1.0);
#define lson l,m, rt<<1
#define rson m+1,r,rt<<1|1
int b[1234],c[1234];
bool vis[123];
int n,a,t,ans;
int gao(int x,int deep)
{
    if(x==0)
    {
        ans=min(ans,deep);
        return 0;
    }
    for(int i=0; i<n&&b[i]<=x; i++)
    {
        if(vis[i]==false)
        {
            vis[i]=true;
            gao(x%b[i],deep+1);
            vis[i]=false;
        }
    }
}
int main()
{
    scanf("%d",&t);

    while(t--)
    {
        memset(vis,false,sizeof(vis));
        scanf("%d%d",&n,&a);
        for(int i=0; i<n; i++)
        {
            scanf("%d",&b[i]);
        }
        sort(b,b+n);
        ans=INF;
        gao(a,0);
        if(ans==INF)
            cout<<-1<<endl;
        else
            cout<<ans<<endl;
    }
    return 0;
}
/*
13 214
1471471471477
*/