#include<bits/stdc++.h>
using namespace std;
int main (){
	int a,b,c,d,e;
	while(cin>>a>>b>>c>>d>>e){
	if(e>d)
	cout<<a*b*c-((a-2*e)*(c-2*e)*d*2+(b-2*e)*(c-2*e)*d*2+(a-2*e)*(b-2*e)*d*2)<<endl;
	else if((a-2*d)*(b-2*d)*(c-2*d)<c*4*e*e+(a-2*e)*e*e*4+(b-2*e)*e*e*4)
	cout<<c*4*e*e+(a-2*e)*e*e*4+(b-2*e)*e*e*4<<endl;
	else
	cout<<(a-2*d)*(b-2*d)*(c-2*d)<<endl;
	}
	return 0;
}