print("Hello")
userInput = int(input("Enter number(-1 to Exit): "))

#Loops unless -1 is entered
while userInput != -1:
    #Prevents user entering a value < -1
    if userInput < -1:
        print("You cannot input a negative value!")
        userInput = int(input("Enter number(-1 to Exit): "))
        
    #Asks user for a new input (Provided -1 has not been typed)
    else:
        userInput = int(input("Enter number(-1 to Exit): "))
              
print("Your total is {0}".format(userInput))
print("Goodbye")