#include <bits/stdc++.h>
using namespace std;
const int maxn = 1e5+10;
int a[maxn];
void solve(){
    int n;
    long long m;
    cin >> n >> m;
    long long sum = 0, x = 0;
    bool flag = 0;
    for (int i = 1; i <= n; i++) {
        scanf("%d", &a[i]);
        sum += a[i];
        x += a[i];
        if (x < 0) x = 0;
        if (x >= m) flag = 1;
    }
    if (flag) {
        puts("1");
        return;
    }
    if (sum <= 0) {
        for (int i = 1; i <= n; i++) {
            x += a[i];
            if (x < 0) x = 0;
            if (x >= m) flag = 1;
        }
        puts(flag?"2":"-1");
        return;
    }else{
        long long mx = 0;
        for (int i = 1; i <= n; i++) {
            x += a[i];
            if (x < 0) x = 0;
            mx = max(mx, x);
        }
        if (mx >= m) puts("2"); else{
            printf("%lld\n", (m - mx + sum - 1) / (sum) + 2);
        }
    }
    
}
int main(){
    int T;
    cin >> T;
    while (T--) solve();
}