#include<bits/stdc++.h>
using namespace std;
#define ll long long
#define db double
#define X first
#define Y second
#define rep(i,a,b) for(int i=(a);i<=(b);++i)
#define rep0(i,a,b) for(int i=(a);i<(b);++i)
#define per(i,a,b) for(int i=(a);i>=(b);--i)
#define fore(i,a) for(int i=0;i<a.size();++i)
inline ll rd()
{
    char c=getchar();ll x=0,w=1;
    while(!isdigit(c)&&c!='-')c=getchar();
    if(c=='-')w=-1,c=getchar();
    while(isdigit(c))x=x*10+c-48,c=getchar();
    return x*w;
}
const int N=100005;
int n;ll m,a[N];
int main()
{
    int T=rd();
    while(T--)
    {
        n=rd();m=rd();
        rep(i,1,n)a[i]=rd();
        ll x=0,ans=0;
        rep(i,1,n)
        {
            x+=a[i];
            if(x>=m){ans=1;break;}
            if(x<0)x=0;
        }
        if(!ans)
        {
            rep(i,1,n)
            {
                x+=a[i];
                if(x>=m){ans=2;break;}
                if(x<0){ans=-1;break;}
            }
            if(!ans)
            {
                ll s=0;
                rep(i,1,n)s+=a[i];
                if(s<=0)ans=-1;
                else
                {
                    rep(i,1,n)
                    {
                        x+=a[i];
                        if(x>=m){ans=3;break;}
                    }
                    x-=s;
                    if(!ans)
                    {
                        ll ss=0;ans=2+m;
                        rep(i,1,n)
                        {
                            ss+=a[i];
                            if(ss<=0)continue;
                            ll t=m-x-ss;
                            ans=min(ans,3+(t+s-1)/s);
                        }
                    }
                }
            }
        }
        printf("%lld\n",ans);
    }
    return 0;
}