#include<stdio.h>

int main()
{
	int a,b,c,d,e,V,v;
	while(scanf("%d %d %d %d %d",&a,&b,&c,&d,&e)!=EOF)
	{
		if(d<e)
		{
			V=a*b*c-((2*d*(c-2*e)*(a-2*e))+2*d*(a-2*e)*(b-2*e)+2*d*(b-2*e)*(c-2*e));
			printf("%d\n",V);
		}
		if(d>=e)
		{
			if(2*d<a&&2*d<b&&2*d<c)
			{
				V=4*(e*e*a+e*e*b+e*e*c)-16*e*e*e;
				v=(a-2*d)*(b-2*d)*(c-2*d);
				if(v>V)
					printf("%d\n",v);
				else printf("%d\n",V);
			}
			else
				{ V=4*(e*e*a+e*e*b+e*e*c)-16*e*e*e;
			     printf("%d\n",V);}
		}
	}

	return 0;
}