通过另一个函数访问一个函数的返回值

Question

I'm kinda new to programming in general, just started to really get into python. And I'm working on a number guesser project.

import random

def main(): # main function
    print("Welcome to the number guesser game")
    range_func()
    max_guess_number(lower_range_cut, upper_range_cut)
    evaluation(random_number, total_guesses)

def range_func():   # allows user to select a range for the number guess
    print("Please select a range in which you would like to guess.")
    lower_range_cut = int(input("Lower boundary limit: "))
    global lower_range_cut
    upper_range_cut = int(input("Upper boundary limit: "))
    global upper_range_cut
    random_number = random.randint(lower_range_cut,upper_range_cut)
    global random_number
    return lower_range_cut, upper_range_cut, random_number

def max_guess_number(low,high): # returns the total number of guesses
    total_numbers = (high - low) + 1
    total_guesses = 0
    while (2**total_guesses) < total_numbers:
        total_guesses += 1
    print ("You have a total of %d guesses\n"
           "for your range between %d to %d"
           % (total_guesses, low, high))
    global total_guesses
    return total_guesses

def evaluation(random_number, total_guesses): # evaluates the users input
    guess_count = 0
    while guess_count < total_guesses:
        user_guess = int(input("Your guess: "))
        print("Your guess is: %d" % (user_guess))
        if (random_number == user_guess):
            print("You got it ")
            break
        elif user_guess > random_number:
            print("Guess lower!")
            guess_count += 1
        else:
            print("Guess higher!")
            guess_count += 1

if __name__ == "__main__":
    main()

One problem I've experienced while writing that, is that I wasn't able to execute this program without redefining each variables as a global variable. Just by returning the values from one function, I was not able to access eg the second returned variable upper_range_cut from the range_function

It there a way to handle that somehow shorter?

Also I'm happy about every note on the code itself (readability, function use, length). I know it could have made this code a lot shorter maybe by using list comprehension, but I don't really have the eye for seeing opportunities in this area yet.

So thanks for any help!

KiliBio

Answer 1

You're pretty much there. You can remove all globals, then just store the values returned from each function to local variables, and pass them in to new functions.

The only other changes I've made below are:

• Breaking out of the evaluation loop if the answer is guessed correctly.
• Printing a message if no guess is found in the given time. See: Else clause on Python while statement
• The bottom two lines allow the script to be run from the command line. See: What does if __name__ == "__main__": do?

Otherwise you're looking good.

import random

def main(): # main function
    print("Welcome to the number guesser game")
    lower, upper, rand = range_func()
    total_guesses = max_guess_number(lower, upper)
    evaluation(rand, total_guesses)

def range_func():   # allows user to select a range for the number guess
    print("Please select a range in which you would like to guess.")
    lower_range_cut = int(input("Lower boundary limit: "))
    upper_range_cut = int(input("Upper boundary limit: "))
    random_number = random.randint(lower_range_cut, upper_range_cut)
    return lower_range_cut, upper_range_cut, random_number

def max_guess_number(low,high): # returns the total number of guesses
    total_numbers = (high - low) + 1
    total_guesses = 0
    while (2**total_guesses) < total_numbers:
        total_guesses += 1
    print ("You have a total of %d guesses\n"
           "for your range between %d to %d"
           % (total_guesses, low, high))

    return total_guesses

def evaluation(random_number, total_guesses): # evaluates the users input
    guess_count = 0
    while guess_count < total_guesses:
        guess_count += 1
        user_guess = int(input("Your guess: "))
        print("Your guess is: %d" % (user_guess))
        if (random_number == user_guess):
            print("You got it!")
            break
    else:
        print "Sorry, you didn't guess it in time. The answer was: %d" % random_number

if __name__ == '__main__':
    main()

Answer 2

You don't need to define global . You can just assign the values you are returning from a function to variable(s).

A simple example:

def add(a, b):
    """This function returns the sum of two numbers"""
    return a + b

Now in your console, you could do following

# print the return
>>> print(add(2, 3))
5

# assign it to a variable
>>> c = add(2, 3)
>>> c
5

In your main function you need to assign the values which are returned by different functions to variables which you can further pass to other functions.

def main(): # main function
    print("Welcome to the number guesser game")
    lower_range_cut, upper_range_cut, random_number = range_func()
    total_guesses = max_guess_number(lower_range_cut, upper_range_cut)
    evaluation(random_number, total_guesses)