#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef pair<int, int> pii;
#define pb push_back
#define all(a) a.begin(), a.end()
#define sz(a) ((int)a.size())
#ifdef Doludu
template <typename T>
ostream& operator << (ostream &o, vector <T> vec) {
    o << "{"; int f = 0;
    for (T i : vec) o << (f++ ? " " : "") << i;
    return o << "}";
}
void bug__(int c, auto ...a) {
    cerr << "\e[1;" << c << "m";
    (..., (cerr << a << " "));
    cerr << "\e[0m" << endl;
}
#define bug_(c, x...) bug__(c, __LINE__, "[" + string(#x) + "]", x)
#define bug(x...) bug_(32, x)
#define bugv(x...) bug_(36, vector(x))
#define safe bug_(33, "safe")
#else
#define bug(x...) void(0)
#define bugv(x...) void(0)
#define safe void(0)
#endif
const int mod = 998244353, N = 1 << 20;

int main() {
    ios::sync_with_stdio(false), cin.tie(0);
    int t;
    cin >> t;
    while (t--) {
        int n, k;
        cin >> n >> k;
        vector <ll> a(n);
        for (int i = 0; i < n; ++i) cin >> a[i];
        sort(all(a));
        a[0] -= k;
        cout << accumulate(all(a), 1ll, [&](ll i, ll j) { return i * j; } ) << "\n";
    }
}