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