#include<iostream>
#include<cstdlib>
#include<cstdio>
#include<cstring>
using namespace std;

int main(){
	int a,b,c,d,e;
	int inner;
	int outer;
	while(cin>>a>>b>>c>>d>>e){
		if(d<e){
			cout<<a*b*c-2*d*(a-2*e)*(b-2*e)-2*d*(b-2*e)*(c-2*e)-2*d*(a-2*e)*(c-2*e)<<endl;
		}
		else{
			inner=(a-2*d)*(b-2*d)*(c-2*d);
			outer=4*e*e*((a-2*e)+(b-2*e)+(c-2*e))+8*e*e*e;
			if(inner<outer)cout<<outer<<endl;
			else cout<<inner<<endl;
		}
	}
}