#include <cstdio>
#include <iostream>
#include <vector>
#include <set>
#include <map>
#include <string>
#include <algorithm>
#include <cmath>

using namespace std;

int main() {
    int t;
    cin >> t;
    while (t--) {
        long long n, m;
        cin >> n >> m;
        vector<long long> a(n);
        int f = 0;
        for (int i = 0; i < n; i++) scanf("%lld", &a[i]);
        long long s = 0;
        for (int i = 0; i < n; i++) {
            s += a[i];
            if (s >= m) {
                cout << "1\n";
                f = 1;
                break;
            }
            if (s < 0) s = 0;
        }
        if (f == 1) continue;
        long long s2 = s;
        for (int i = 0; i < n; i++) {
            s2 += a[i];
            if (s2 >= m) {
                cout << "2\n";
                f = 1;
                break;
            }
            if (s2 < 0) s2 = 0;
        }
        if (f == 0) {
            if (s2 <= s) {
                cout << "-1\n";
            }
            else {
                long long mx = -1;
                long long tmp = 0;
                for (int i = 0; i < n; i++) {
                    tmp += a[i];
                    mx = max(mx, tmp);
                }
                cout << (m - mx - s - 1) / (s2 - s) + 3 << endl;
            }
        }
    }
    return 0;
}