#include<fstream>
#include<algorithm>
using namespace std;
int n,m,i,j,nr,b[5];
float a[100],a1,b1,c1,s,x;
int main()
{
	ifstream f("minim2.in");
	ofstream g("minim2.out");
	f>>n;
	for(i=1;i<=n;i++)
	{
		f>>a[i];
		s=s+a[i];
	}
	
	f>>a1>>b1>>c1;
		sort(a+1,a+n+1);
		a[n]=a[n]*a1;
		nr=1;
		i=n;
		while(s>=c1)
		{
			if((a[i]-(a[i]*b1))>(a[i-1]-(a[i-1]*b1)))
			{
				a[i]=a[i]*b1;
				s=s-a[i];
				//a[i]=a[i]*b1;
				//nr++;
				
			}
			else
				if((a[i]-(a[i]*b1))<(a[i-1]-(a[i-1]*b1)))
				{
					   a[i-1]=a[i-1]*b1;
					   s=s-a[i];
				       //a[i-1]=a[i-1]*b1;
				        // nr++;
						i--;
					
				}
					//i--;
				nr++;
		}
		
				
		
		g<<nr;
	
}