#include<bits/stdc++.h>
using namespace std;
int main ()
{
	int v1,v2;
	int a,b,c,d,e;
	int t;
	while(scanf("%d %d %d %d %d",&a,&b,&c,&d,&e)!=EOF)
	{
		int v0=a*b*c-(a-2*e)*d*2*(c-2*e)-(b-2*e)*d*2*(c-2*e)-(a-2*e)*d*2*(b-2*e);
		if(d<e)
		printf("%d\n",v0);
		else 
		{
			v1=(b-2*d)*(c-2*d)*(a-2*d);
			v2=e*a*e*4+e*e*(c-2*e)*4+e*e*(b-2*e)*4;
			if(b-2*d<=0||c-2*d<=0||a-2*d<=0)
			printf("%d\n",v2);
			else
			{
			if(v1<v2)
			printf("%d\n",v2);
			else 
			printf("%d\n",v1);
			}
		}
	}		
}