//#pragma GCC optimize("Ofast")
//#pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx,avx2,fma")
//#pragma GCC optimize("unroll-loops")
#include<bits/stdc++.h>
#define N 100005
#define inf 2147483647
#define LL long long
using namespace std;
int T,n,pos[N],a[N];LL m,S[N],pre[N];
struct FastIO{
    static const int S=1048576;
    char buf[S],*L,*R;int stk[20],Top;~FastIO(){clear();}
    inline char nc(){return L==R&&(R=(L=buf)+fread(buf,1,S,stdin),L==R)?EOF:*L++;}inline void clear(){fwrite(buf,1,Top,stdout);Top=0;}
    inline void pc(char ch){Top==S&&(clear(),0);buf[Top++]=ch;}inline void endl(){pc('\n');}
    FastIO& operator >> (char&ch){while(ch=nc(),ch==' '||ch=='\n');return *this;}
    template<typename T>FastIO& operator >> (T&ret){
        ret=0;int f=1;char ch=nc();while(ch<'0'||ch>'9'){if(ch=='-')f=-f;ch=nc();}
        while(ch>='0'&&ch<='9'){ret=ret*10+ch-'0';ch=nc();}ret*=f;return *this;
    }
    FastIO& operator >> (char* s){int Len=0;char ch=nc();while(ch!='\n'){*(s+Len)=ch;Len++;ch=nc();}}
    template<typename T>FastIO& operator << (T x){
        if(x<0){pc('-');x=-x;}do{stk[++stk[0]]=x%10;x/=10;}while(x);
        while(stk[0]) pc('0'+stk[stk[0]--]);return *this;
    }
    FastIO& operator << (char ch){pc(ch);return *this;}
    FastIO& operator << (string str){int Len=str.size()-1;for(stk[0]=0;Len>=0;Len--) stk[++stk[0]]=str[Len];while(stk[0]) pc(stk[stk[0]--]);return *this;}
}fin,fout;
int main(){
//    freopen("data.in","r",stdin);
//    freopen("jxc.out","w",stdout);
    fin>>T;while(T--){
        fin>>n>>m;for(register int i=1;i<=n;i++) fin>>a[i],S[i]=S[i-1]+a[i],pre[i]=max(pre[i-1],S[i]);bool flg=0;int tot=0;
        LL now=0;for(register int i=1;i<=n;i++){now+=a[i];if(now<0) now=0,pos[++tot]=i;if(now>=m){flg=1,puts("1");break;}} 
        if(flg) continue;if(!now){puts("-1");continue;}
        for(register int i=1;i<=tot;i++){if(now+S[pos[i]]<=0){if(now+pre[pos[i]-1]>=m) puts("2");else puts("-1");flg=1;break;}}if(flg) continue;
        if(now+pre[n]>=m) puts("2");else cout<<2+(LL)ceil(1.0*(m-now-pre[n])/S[n])<<'\n';
//            LL tim=0;if(X+max(suf[pos[i]+1],pre[pos[i]-1])>=m) tim=1;else tim=(LL)ceil(1.0*(m-X-max(suf[pos[i]+1],pre[pos[i]-1]))/now)+1;
//            if(tim<=max((LL)ceil(1.0*(abs(S[i])-X)/now),0ll)){flg=1,cout<<x+tim<<'\n';break;} x+=max((LL)ceil(1.0*(abs(S[i])-X)/now),0ll),X=now*x;
//        if(flg) continue;if(X+pre[n]>=m) cout<<x+1<<'\n';else cout<<x+(LL)ceil(1.0*(m-X-pre[n])/S[n])+1<<'\n';
//        cout<<now<<'\n';LL x=(LL)ceil(1.0*(m-Max)/now);cout<<x+1<<'\n';
    }
    return 0;
}