count=0

print("Hello")
number=int(input("Please input a number. If you wish to quit please enter -1 "))
if(number<-1):
    number=0
    print("You cannot enter minus numbers")

while(number!=-1):
    final=count+number
    count=final
    number=int(input("Please input a number. If you wish to quit please enter -1 "))
    if(number<-1):
        number=0
        print("You cannot enter minus numbers")

else:
    print("your total is {0}".format(final))
    print("Goodbye")