#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(d<e)
	{
	printf("%d\n",a*b*c-(2*((a-2*e)*(c-2*e)*d+(b-2*e)*(c-2*e)*d+(a-2*e)*(b-2*e)*d)));
	}
	else
	{
		if((e*e*e*8+(a-2*e)*e*e*4+(b-2*e)*e*e*4+(c-2*e)*e*e*4)>=((a-2*d)*(b-2*d)*(c-2*d)))
			printf("%d\n",e*e*e*8+(a-2*e)*e*e*4+(b-2*e)*e*e*4+(c-2*e)*e*e*4);
		else
			printf("%d\n",(a-2*d)*(b-2*d)*(c-2*d));
	}
	}
	return 0;
}