#include <cstdio>
#include <queue>
#include <algorithm>
using namespace std;

int main()
{
	priority_queue <double> heap;
	int n,i,cont;
	double x,record,suma=0,a,b;
	freopen("minim2.in","r",stdin);
	freopen("minim2.out","w",stdout);
	scanf("%d",&n);
	for(i=1; i<=n; i++) {
		scanf("%lf",&x);
		suma+=x;
		heap.push(x);
	}
	scanf("%lf %lf %lf",&a,&b,&record);
	if(suma<record) printf("0\n");
	else {
		x=heap.top();
		x=heap.top();
		heap.pop();
		suma-=x;
		x=x*a;
		suma+=x;
		heap.push(x);
		for(cont=1; suma>record; cont++) {
			x=heap.top();
			heap.pop();
			suma-=x;
			x=x*b;
			suma+=x;
			heap.push(x);
		}
		--cont;
		printf("%d\n",cont);
	}
	return 0;
}