#include<stdio.h>
int main(){
	int a,b,c,d,e,x,y,z,v1,v2,v3,end;
	while(scanf("%d%d%d%d%d",&a,&b,&c,&d,&e)!=EOF){
		x=a-2*e;
		y=b-2*e;
		z=c-2*e;
		v1=a*b*c-x*y*d*2-x*z*d*2-y*z*d*2;
		v2=(a-2*d)*(b-2*d)*(c-2*d);
		v3=4*e*e*c+4*e*e*x+4*e*e*y;
		if(d<e){
			end=v1;
		}
		else if(d>=e&&v2>v3){
			end=v2;
		}
		else if(d>=e&&v3>v2){
			end=v3;
		}
		printf("%d\n",end);
	}
	return 0;
}