#include<iostream>
#include<algorithm>
#include<cstdio>
#include<cstring>
#include<string>
#include<cmath>
using namespace std;
int main()
{
	int a,b,c,d,e;
	while(cin>>a>>b>>c>>d>>e)
	{
		int s=0;
		if(d<e) s=a*b*c-d*(a-2*e)*(c-2*e)*2-d*(b-2*e)*(c-2*e)*2-d*(a-2*e)*(b-2*e)*2;
		else 
		{
			if(d*2>a||d*2>b||d*2>c) s=8*e*e*e+(a-2*e)*e*e*4+(b-2*e)*e*e*4+(c-2*e)*e*e*4;
			else s=max(8*e*e*e+(a-2*e)*e*e*4+(b-2*e)*e*e*4+(c-2*e)*e*e*4,(a-2*d)*(b-2*d)*(c-2*d));
		}
		printf("%d\n",s);
	}
}