#include <bits/stdc++.h>
using namespace std;
 
typedef long long int ll;
 
void solve() {
    ll n, c;
    cin >> n >> c;
 
    // Use vector instead of VLA to prevent stack overflow
    vector<ll> b(n + 1, 0);
    ll sum = 0;
 
    for (ll i = 1; i <= n; i++) {
        cin >> b[i];
        sum += b[i];
    }
 
    // Sort from index 2 to n
    sort(b.begin() + 2, b.end());
 
    ll answer = 0;
 
    // Precompute prefix sums for the sorted region to achieve O(1) range queries
    vector<ll> pref(n + 1, 0);
    for (ll i = 2; i <= n; i++) {
        pref[i] = pref[i - 1] + b[i];
    }
 
    // Single loop: O(N) instead of O(N^2)
    for (ll do_it = 1; do_it <= n - 1; do_it++) {
        // 1. Sum of the smallest 'do_it' elements starting from index 2
        ll sum_low = pref[1 + do_it]; 
        ll u1 = (sum - sum_low) * sum_low;
 
        // 2. Sum of the largest 'do_it' elements ending at index n
        ll sum_high = pref[n] - pref[n - do_it];
        u1 = min(u1, (sum - sum_high) * sum_high);
 
        if (u1 <= c) {
            answer = do_it;
        }
    }
 
    cout << n - answer << "\n";
}
 
int main() {
    // Fast I/O optimization
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);
 
    ll t;
    cin >> t;
    while (t--) {
        solve();
    }
    return 0;
}

I2luY2x1ZGUgPGJpdHMvc3RkYysrLmg+CnVzaW5nIG5hbWVzcGFjZSBzdGQ7Cgp0eXBlZGVmIGxvbmcgbG9uZyBpbnQgbGw7Cgp2b2lkIHNvbHZlKCkgewogICAgbGwgbiwgYzsKICAgIGNpbiA+PiBuID4+IGM7CiAgICAKICAgIC8vIFVzZSB2ZWN0b3IgaW5zdGVhZCBvZiBWTEEgdG8gcHJldmVudCBzdGFjayBvdmVyZmxvdwogICAgdmVjdG9yPGxsPiBiKG4gKyAxLCAwKTsKICAgIGxsIHN1bSA9IDA7CiAgICAKICAgIGZvciAobGwgaSA9IDE7IGkgPD0gbjsgaSsrKSB7CiAgICAgICAgY2luID4+IGJbaV07CiAgICAgICAgc3VtICs9IGJbaV07CiAgICB9CiAgICAKICAgIC8vIFNvcnQgZnJvbSBpbmRleCAyIHRvIG4KICAgIHNvcnQoYi5iZWdpbigpICsgMiwgYi5lbmQoKSk7CiAgICAKICAgIGxsIGFuc3dlciA9IDA7CiAgICAKICAgIC8vIFByZWNvbXB1dGUgcHJlZml4IHN1bXMgZm9yIHRoZSBzb3J0ZWQgcmVnaW9uIHRvIGFjaGlldmUgTygxKSByYW5nZSBxdWVyaWVzCiAgICB2ZWN0b3I8bGw+IHByZWYobiArIDEsIDApOwogICAgZm9yIChsbCBpID0gMjsgaSA8PSBuOyBpKyspIHsKICAgICAgICBwcmVmW2ldID0gcHJlZltpIC0gMV0gKyBiW2ldOwogICAgfQogICAgCiAgICAvLyBTaW5nbGUgbG9vcDogTyhOKSBpbnN0ZWFkIG9mIE8oTl4yKQogICAgZm9yIChsbCBkb19pdCA9IDE7IGRvX2l0IDw9IG4gLSAxOyBkb19pdCsrKSB7CiAgICAgICAgLy8gMS4gU3VtIG9mIHRoZSBzbWFsbGVzdCAnZG9faXQnIGVsZW1lbnRzIHN0YXJ0aW5nIGZyb20gaW5kZXggMgogICAgICAgIGxsIHN1bV9sb3cgPSBwcmVmWzEgKyBkb19pdF07IAogICAgICAgIGxsIHUxID0gKHN1bSAtIHN1bV9sb3cpICogc3VtX2xvdzsKICAgICAgICAKICAgICAgICAvLyAyLiBTdW0gb2YgdGhlIGxhcmdlc3QgJ2RvX2l0JyBlbGVtZW50cyBlbmRpbmcgYXQgaW5kZXggbgogICAgICAgIGxsIHN1bV9oaWdoID0gcHJlZltuXSAtIHByZWZbbiAtIGRvX2l0XTsKICAgICAgICB1MSA9IG1pbih1MSwgKHN1bSAtIHN1bV9oaWdoKSAqIHN1bV9oaWdoKTsKICAgICAgICAKICAgICAgICBpZiAodTEgPD0gYykgewogICAgICAgICAgICBhbnN3ZXIgPSBkb19pdDsKICAgICAgICB9CiAgICB9CiAgICAKICAgIGNvdXQgPDwgbiAtIGFuc3dlciA8PCAiXG4iOwp9CgppbnQgbWFpbigpIHsKICAgIC8vIEZhc3QgSS9PIG9wdGltaXphdGlvbgogICAgaW9zX2Jhc2U6OnN5bmNfd2l0aF9zdGRpbyhmYWxzZSk7CiAgICBjaW4udGllKE5VTEwpOwogICAgCiAgICBsbCB0OwogICAgY2luID4+IHQ7CiAgICB3aGlsZSAodC0tKSB7CiAgICAgICAgc29sdmUoKTsKICAgIH0KICAgIHJldHVybiAwOwp9

NAozIDEwMDAwMDAwMDAwMDAwMDAwMDAKMjAwMDAwMCA0MDAwMDAwIDUwMDAwMDAKNCAxNTAKMTAwIDEgMSAxCjYgMTI3NQozNSAxNSAxMCAyNSAxMCA1CjYgNDAwCjM1IDE1IDEwIDI1IDEwIDU=

4
3 1000000000000000000
2000000 4000000 5000000
4 150
100 1 1 1
6 1275
35 15 10 25 10 5
6 400
35 15 10 25 10 5