#include<iostream>

using namespace std;

int check(int mid, int N, int W, int H, int a[])

{

int page = 0;

int w = W / mid;

int h = H / mid;

int p_w,p_w_y,hang=0;

for(int i=0;i<N;i++){

p_w = a[i] / w;

p_w_y = a[i] % w;

hang = hang + p_w;

if(p_w_y != 0)hang ++;

}

page = hang / h;

if(hang % h != 0)page ++;

return page;

}

int main()

{

int mid = 0;

int n,T,N,P,W,H,ans=0,cnt;

int a[100];

while(cin>>n){

for(int T=1;T<=n;T++){

cin>>N>>P>>W>>H;

for(int i=0;i<N;i++)

{

cin >> a[i];

}

int left=1, right=min(W,H);

while(left <= right){

mid = (left + right) / 2;

cnt = check(mid, N, W, H, a);

if(cnt > P){

right = mid - 1;

}else{

ans = mid;

left = mid + 1;

}

}

cout<<ans<<endl;

}

}

return 0;

}