#include <cstdio>
#include <iostream>
#include<string>
#include<algorithm>
using namespace std;

int main()
{
   int a,b,c,d,e,f,ans;
   while(~scanf("%d%d%d%d%d",&a,&b,&c,&d,&e))
   {
	   ans=0;
	   int tot=a*b*c;
	   int minus=(a-2*e)*(c-2*e)*d*2+(b-2*e)*(c-2*e)*d*2+(a-2*e)*(b-2*e)*d*2;
	   int kuang=e*e*(a-2*e+b-2*e+c-2*e)*4+e*e*e*8;
	   int neibu=(b-2*d)*(a-2*d)*(c-2*d);
	  if(d<e)
	  {
		  ans=tot-minus;
		  cout<<ans<<endl;
	  }
	  else if(d>=e)
	  {
		  if(kuang>=neibu)
			  cout<<kuang<<endl;
		  else
			  cout<<neibu<<endl;
	  }
   }
}