#pragma GCC optimize("Ofast")
#include<bits/stdc++.h>
#define int long long
using namespace std;
void fileio(const string &s)
{
    freopen((s+".in").c_str(),"r",stdin);
    freopen((s+".out").c_str(),"w",stdout);
}
const int INF=4e18;
inline int read()
{
    int x=0;
    bool flag=1;
    char c=getchar();
    while(c<'0'||c>'9')
    {
        if(c=='-')
            flag=0;
        c=getchar();
    }
    while(c>='0'&&c<='9')
    {
        x=(x<<1)+(x<<3)+c-'0';
        c=getchar();
    }
    return (flag?x:~(x-1));
}
int t,minn,maxx,n,k,sum,cnt,a[100001];
void solve()
{
    n=read();
    k=read();
    minn=0;
    maxx=0;
    cnt=0;
    sum=0;
    for(int i=1;i<=n;i++)
    {
        a[i]=read();
        sum+=a[i];
        minn=min(minn,sum);
        maxx=max(maxx,sum);
    }
    for(int i=1;i<=n;i++)
    {
        cnt=max(0ll,cnt+a[i]);
        if(cnt>=k)
        {
            puts("1");
            return ;
        }
    }
    for(int i=1;i<=n;i++)
    {
        cnt=max(0ll,cnt+a[i]);
        if(cnt>=k)
        {
            puts("2");
            return ;
        }
    }
    if(cnt+minn<=0)
    {
        puts("-1");
        return ;
    }
    if(sum<0)
    {
        puts("-1");
        return ;
    }
    cout<<(k-maxx-cnt+sum-1)/sum+3<<endl;
}
signed main()
{
    t=read();
    while(t--)
        solve();
    return 0;
}