#include<cstdio>

#include<cmath>
#include<cstring>
#include<algorithm>
using namespace std;
int main()
{
	int a,b,c,d,e,s1,s2,s;
	while(~scanf("%d%d%d%d%d",&a,&b,&c,&d,&e))
	{
	  if(d<e)
	  {
	  s2=2*d*(a-(2*e))*(c-(2*e))+2*d*(b-(2*e))*(c-(2*e))+2*d*(a-(2*e))*(b-(2*e));
	  s=a*b*c-s2;
	  }
      else 
	  {
		s1=(a-2*d)*(b-2*d)*(c-2*d);
		s2=4*(a-2*e)*e*e+4*(b-2*e)*e*e+4*(c-2*e)*e*e+8*e*e*e;
		if(s1>s2)
			s=s1;
		else
		    s=s2;
	  }
	  printf("%d\n",s);
	}
//	system("pause");
}