#include<stdio.h>

int main()
{
	int a,b,c,d,e,V1,V2,x;
	
	while(scanf("%d %d %d %d %d",&a,&b,&c,&d,&e)!=EOF)
	{
	
	V1=a*b*c-2*(a-2*e)*(c-2*e)*d-2*(b-2*e)*(c-2*e)*d-2*(a-2*e)*(b-2*e)*d;
	V2=4*e*e*c+4*e*e*(a-2*e)+4*e*e*(b-2*e);
    x=(a-2*d)*(b-2*d)*(c-2*d);
    
	if(e>d)
		printf("%d\n",V1);
	if(e<=d&&V2>x)
		printf("%d\n",V2);
	if(e<=d&&V2<=x)
		printf("%d\n",x);
	}
	 
	return 0;
}