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