#include<stdio.h>
#include<math.h>
int main(){
	int a,b,c,d,e;
	while(scanf("%d %d %d %d %d",&a,&b,&c,&d,&e)!=EOF){
	int qian=0,shang=0,zuo=0,q=0,v=0,vk=0,v1=0;	
	if(d>=e){
		vk=e*e*a*4+e*e*(c-2*e)*4+e*e*(b-2*e)*4;
		v1=(a-2*d)*(b-2*d)*(c-2*d);
		if(vk>v1)
			v=vk;
		else
			v=v1;	
	}
	else{
		qian=(a-2*e)*(c-2*e)*d*2;
		shang=(a-2*e)*(b-2*e)*d*2;
		zuo=(b-2*e)*(c-2*e)*d*2;
		q=qian+shang+zuo;
		v=a*b*c-q;
	}
	printf("%d\n",v);
	}				
	return 0;
}