#include<stdio.h>
#include<math.h>
int main(){
	int a,b,c,d,e;
	int v1,v2,v3,v4,v5;
			while(scanf("%d %d %d %d %d",&a,&b,&c,&d,&e)!=EOF){
			v1=(a-2*e)*(c-2*e)*d;
			v2=(a-2*e)*(b-2*e)*d;
			v3=(b-2*e)*(c-2*e)*d;
			if(d<e) v4=a*b*c-(v1+v2+v3)*2;
			else v4=4*e*e*(a-2*e)+4*e*e*(b-2*e)+4*e*e*(c-2*e)+8*e*e*e;
			v5=(a-2*d)*(c-2*d)*(b-2*d);
            if(v4>v5)
			printf("%d\n",v4);
            else
			printf("%d\n",v5);
			}
}