rt

#include <bits/stdc++.h>
using namespace std;
long long a,b,c,d,e,f,k;
int main(){
    cin>>a>>b>>c>>d>>e>>f>>k;
    cout<<max(floor(1.0*k/b)*a*c,floor(1.0*k/e)*d*f)<<endl;
    return 0;
}