#include<stdio.h>
int main(){
	int a,b,c,d,e,i,m[3],x,v,n,f,k;
	while(scanf("%d %d %d %d %d",&a,&b,&c,&d,&e)!=EOF){
		m[0]=a;
		m[1]=b;
		m[2]=c;
		for(i=0;i<3;i++){
			if(m[i+1]<m[i]){
				m[i]=m[i+1];
			}
		}
		x=m[0]/2;
		if(e>0&&e<x&&0<d){
			n=(a*b*c)-(a-(2*e))*d*(c-(2*e))*2-(b-(2*e))*d*(c-(2*e))*2-(a-(2*e))*d*(b-(2*e))*2;
			f=(a-(2*d))*(b-(2*d))*(c-(2*d));
			k=(a*b*e-(a-2*e)*(b-2*e)*e)*2+(c-2*e)*e*e*4;
			if(d<e){
				v=n;				
			}else if(k>f){
				v=k;
			}else if(k<f){
				v=f;
			}	
			printf("%d\n",v);
		}
	}
	return 0;
}