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

#define ll long long 
#define INF 0x3f3f3f3f
#define LNF 0x3f3f3f3f3f3f3f3fll
#define MOD 998244353
#define pii pair<int, int>

#define N 100010
#define K 20

ll val(ll x, ll k) {
    return (x + k - 1) / k * k - x;
}

int main() {
#ifdef TEST
    freopen("zz.in", "r+", stdin);
#endif
    ios::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);

    int t; cin >> t;
    while (t --) {
        int n, k; cin >> n >> k;
        vector<int> a(n+5);
        for (int i = 1; i <= n; ++ i) cin >> a[i];

        vector<int> ord(n);
        iota(ord.begin(), ord.end(), 1);
        sort(ord.begin(), ord.end(), [&](auto x, auto y) {
            return val(a[x], k) < val(a[y], k);
        });

        int m; cin >> m;
        for (auto idx : ord) {
            int d = min(m, (int) val(a[idx], k));
            a[idx] += d, m -= d;
        }

        ll res = m / k;
        for (int i = 1; i <= n; ++ i) res += a[i] / k;
        cout << res << '\n';
    }
}