#include <bits/stdc++.h>
using namespace std;

const int mod= 998244353;
typedef long long ll;
const ll inf = 1e18+100;

const int maxn = 1e5+5;

int a[maxn];
ll sum[maxn],sum2[maxn],sum3[maxn];
int main(){
    int t;
    scanf("%d",&t);
    while(t--){
        int n;ll m;
        scanf("%d%lld",&n,&m);
        ll ans=0;
        for(int i=1;i<=n;++i){
            scanf("%d",&a[i]);
            sum[i]=(sum[i-1]+a[i]);
            if(sum[i]<0)sum[i]=0;
            else if(sum[i]>=m){
                ans=1;
            }
        }
        if(ans)printf("%lld\n",ans);
        else{
            for(int i=1;i<=n;++i){
                if(i==1)sum2[1]=(sum[n]+a[i]);
                else sum2[i]=(sum2[i-1]+a[i]);
                if(sum2[i]<0)sum2[i]=0;
                else if(sum2[i]>=m){
                    ans=2;
                    break;
                }
                if(sum2[i]==sum[i]){
                    ans=-1;
                    break;
                }
            }
            if(ans)printf("%lld\n",ans);
            else{
                for(int i=1;i<=n;++i){
                    if(i==1)sum3[1]=(sum2[n]+a[i]);
                    else sum3[i]=(sum3[i-1]+a[i]);
                    if(sum3[i]<0)sum3[i]=0;
                    else if(sum3[i]>=m){
                        ans=3;
                        break;
                    }
                    if(sum3[i]==sum2[i]){
                        ans=-1;
                        break;
                    }
                }
                if(ans){
                    printf("%lld\n",ans);
                }else{
                    ans=inf;
                    for(int i=1;i<=n;++i){
//                        printf("%lld %lld\n",sum2[i],sum3[i]);
                        ans=min(ans,(m-sum2[i]-1)/(sum3[i]-sum2[i])+3);
                    }
                    printf("%lld\n",ans);
                }
            }
        }
    }
}