#include<bits/stdc++.h>
using namespace std;
#define int long long
#define endl '\n'
#define io ios::sync_with_stdio(false),cin.tie(0),cout.tie(0)
#define all(a) a.begin(),a.end()
typedef pair<int,int> PII;
typedef long long LL;
const int N = 2e5 + 10;
const int mod = 998244353;
inline int ls(int x) { return x << 1; }
inline int rs(int x) { return x << 1 | 1; }
int dx[8] = { 1,0,0,-1,-1,-1,1,1 };
int dy[8] = { 0,-1,1,0,-1,1,-1,1};
inline int gcd(int a, int b)
{
   if (b) while ((a %= b) && (b %= a));
   return a + b;
}
void solve()
{
    int n,k;
    cin >> n >> k;
    vector<int>a(n + 1);
    int ans = 0;
    for(int i = 1;i <= n;i++) {
        cin >> a[i];
        ans += a[i] / k;
        a[i] %= k;
        a[i] = k - a[i];
    }
    int m;
    cin >> m;
    for(int i = 1;i <= n;i++){
        if(m >= a[i]){
            m -= a[i];
            ans++;
        }
    }
    ans += m / k;
    cout << ans << endl;
}
signed main()
{
    io;
    int tt = 1;
    cin >> tt;
    while(tt--)
    {
        solve();
    }
	return 0;
}