#include <bits/stdc++.h>
#define NAME "b"
using namespace std;
typedef long long ll;
typedef unsigned long long ull;
typedef double db;
typedef long double ldb;
const int N = 1000006;
const int MOD = 1000000007;

int testCase;
int n;
ll k, m;

bool cmp(ll a, ll b) {
	return (a % k) > (b % k);
}

void process() {
	ll ans = 0;
	cin >> n >> k;
	vector<ll> arr(n);
	for (int i = 0; i < n; i++) cin >> arr[i];
	cin >> m;
	sort(arr.begin(), arr.end(), cmp);
	for (int i = 0; i < n; i++) {
		ll t = (ll)k - arr[i] % (ll)k;
		if (t == k) t = 0;
		if (m - t >= 0) {
			arr[i] += t;
			m -= t;
		}
		else {
			arr[i] += m;
			m = 0;
		}
		if (i == n - 1) arr[i] += m;
		ans += (arr[i] / k);
	}
	cout << ans << "\n";
}

int main() {
	ios_base::sync_with_stdio(false);
	cin.tie(0); cout.tie(0);
#ifndef ONLINE_JUDGE
	freopen(NAME".inp", "r", stdin);
	freopen(NAME".out", "w", stdout);
#endif
	cin >> testCase;
	while (testCase--) process();
	return 0;
}