#include<iostream>
#include<algorithm>

using namespace std;

int main(){
	int a,b,c,d,e;
	int m1,m2;

	while(scanf("%d%d%d%d%d",&a,&b,&c,&d,&e)!=EOF){
		if(d<e){
			m1=a*b*c-((c-e*2)*(a-e*2)*d)*2-((b-e*2)*(c-e*2)*d)*2-((b-e*2)*(a-e*2)*d)*2;
			printf("%d\n",m1);
		}else{
			m2=(a-d*2)*(b-d*2)*(c-d*2);
			m1=(b-e*2)*e*e*4+(a-e*2)*e*e*4+(c-e*2)*e*e*4+e*e*e*8;
			printf("%d\n",max(m1,m2));
		}

	}

	return 0;
}