#include <bits/stdc++.h>
using namespace std;

long long a[100010];

int main() {
    int T; scanf("%d", &T);
    int Case = 0;
    while (T--) {
        Case++;
        int n; long long m; scanf("%d%lld", &n, &m);
        long long sum = 0, minj = 0;
        for (int i = 1; i <= n; i++) {
            scanf("%lld", &a[i]);
        }
        long long maxj = 0, x;
        for (int i = 1; i <= n; i++) {
            sum += a[i];
            minj = min(minj, sum);
            maxj = max(maxj, sum);
            if (sum - minj >= m) {
                printf("1\n");
                goto END;
            }
        }
        x = sum - minj;
        if (x + minj <= 0 || sum <= 0) {
            for (int i = 1; i <= n; i++) {
                x += a[i];
                if (x < 0) x = 0;
                if (x >= m) {
                    printf("2\n");
                    goto END;
                }
            }
            printf("-1\n");
            goto END;
        } else {
            long long lim = m - maxj;
            printf("%lld\n", max(0ll, (lim - x + sum - 1) / sum) + 1 + 1);
        }
        END:;
    }
    return 0;
}