#include<bits/stdc++.h>
using namespace std;
#define ll long long
#define pb push_back
#define fi first
#define se second
typedef vector<vector<ll>> Mat;
#define int long long
const int N=1e6+10,mod=1e9+7,inf=1e9+1,P=998244353;
const double pi=acos(-1.0),esp=1e-9;
const ll INF=1e18;
void solve()
{
	int n,k;
	cin>>n>>k;
	vector<int>a(n+1);
	for(int i=1;i<=n;i++){
		cin>>a[i];
	}
	int m;
	cin>>m;
	sort(a.begin()+1,a.end(),[&](int x,int y){
		return x%k>y%k;
	});
	for(int i=1;i<=n;i++){
		int t=min(m,(k-a[i]%k)%k);
		m-=t;
		a[i]+=t;
	}
	int ans=m/k;
	for(int i=1;i<=n;i++)ans+=a[i]/k;
	cout<<ans<<'\n';
}
signed main()
{
    ios::sync_with_stdio(false);
    cin.tie(0);cout.tie(0);
    int t=1;
    cin>>t;
    while(t--)
        solve();
    return 0;
}