#Task 1
#print("Hello")
#userinput = 0
#sum1 = 0
#while userinput != -1:
#    userinput = int(input("Enter number (-1 to exit):"))
#    if userinput != -1:
#        sum1 = sum1 + userinput
#print("Your total is:", format(sum1))
#print("Goodbye")

#Task 2

print("Hello")
userinput = 0
sum1 = 0
while userinput != -1:
    userinput = int(input("Enter number (-1 to exit):"))
    if userinput < -1:
        print("You cannot input a negative number!")
    else:
        if userinput != -1:
            sum1 = sum1 + userinput
print("Your total is:", format(sum1))
print("Goodbye")