（python）在让用户输入内容之前如何检查while循环的有效性？

Question

import random

numberList = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 'jack', 'queen', 'king']
total = 0

while total <= 21:
    output = random.choice(numberList)
    if output == 'jack' or output == 'queen' or output == 'king':
        print(f'({output})')
        output = 10

    print(f'you got {output} points')
    total += output

    ask_cont = input(f'you now have {total} points, continue? [y/n]: ').lower()
    if ask_cont == 'y':
        continue
    else:
        print(f'game finished. You gain {total} points!')
        break
else:
    print(f'you lost! points exceeded = {total - 21} points!')

I am coding a blackjack game. However, in the while loop (condition: total amount at hand <= 21), when it exceeded 21 points, it still ask me to continue (ask_cont variable) or not [y/n] for ONCE before code finished and if I type 'n', it just give me the current points (>21) and the 'game finished' statement. How can I fix this? Thank you very much

(also, if there is any way to trim the code please comment, many thanks!)

Answer 1

First of all, don't worry about your code being too verbose. It's better to have long, readable code, than short, hard to decipher code. Your code looks just fine.

As far as preventing the user from continuing if total > 21 , this is because you are adding to the total total += output before you get to the while total <= 21 . To fix this, you just have two options.

The first is to have it ask at the start of the while loop, before points are added. If you do this, you would also have it ask once before the while loop starts. Normally you would do this using a do..while loop, but python doesn't have those.

The second optional would be to just add an extra if statement, where it only asks you to continue if total <= 21 , otherwise it does something that finishes the game with the exceed message.