#include<fstream>
#include<algorithm>
using namespace std;
int a[100],n,m,i,j,nr,b[5];
float 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))
			{
				s=s-(a[i]-a[i]*b1);
//<<s<<"\n";
				a[i]=a[i]*b1;
				//g<<a[i]<<"\n";
				nr++;
				
			}
			else
				if((a[i]-a[i]*b1)<(a[i-1]-a[i-1]*a1))
				{
					   s=s-(a[i-1]-a[i-1]*a1);
					  // g<<s<<"\n";
				       a[i-1]=a[i-1]*a1;
					//   g<<a[i]<<"\n";
				         nr++;
					
				}
					i--;
				
		}
		
				
		
		g<<nr;
	
}