#include <bits/stdc++.h>
using namespace std;
int main() {
int a,b,c,d,e;
while(cin>>a>>b>>c>>d>>e){
if(d<e){
cout<<a*b*c-2*(a-2*e)*(c-2*e)*d-2*(b-2*e)*(c-2*e)*d-2*(b-2*e)*(a-2*e)*d<<endl;
}
else{
int v1,v2;
v1=a*b*c - (a - 2 * e)*(c - 2 * e)*b - 2 * (b - 2 * e)*(c - 2 * e)*e - 2 * (b - 2 * e)*(a - 2 * e)*e;
v2=(a-2*d)*(c-2*d)*(b-2*d);
cout<<max(v1,v2)<<endl;
}
}
}