while 1:
    try:
        a,b,c,d,e=map(int,input().split())
        if d<e:
            v1=a*b*c-2*(d*(a-2*e)*(c-2*e)+d*(b-2*e)*(c-2*e)+d*(a-2*e)*(b-2*e))
            print(v1)
        else :
            v3=4*e*e*c+4*e*e*(a-2*e)+4*e*e*(b-2*e)
            if a-2*d<0 or b-2*d<0 or c-2*d<0:
                print(v3)
            else:
                v2=(a-2*d)*(b-2*d)*(c-2*d)
                if v3>v2:
                   print(v3)
                else:
                   print(v2)
    except:
        break