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