How do I replace a value in a list corresponding to the user's input?

Question

So I'm new to python and I'm making a tic tac toe game and for each players turn you pick a number from 0–8. It checks if it's an integer between 0–8, but I wanted to be able to take the response and replace the corresponding number in the list.

For instance, say my list looked like this

tiles = [0, 1, 2, 3, 4, 5, 6, 7, 8]

and for X's turn they typed 1.

I want it to replace 1 with an X on the board. I know I could do this with a whole bunch of if/elif/else statements but my friend did that and it looked super long and unnecessary.

I put it on GitHub in case you wanted to have look at the code to better understand what I'm talking about.

I'm using repl.it so I'm stuck on 3.8.2.

What tutorial are you reading that teaches lists but doesn't teach how to set list elements? — Kelly Bundy, Feb 24 '22 at 16:24
@KellyBundy [Finding the index of an item in a list](https://stackoverflow.com/q/176918/6045800) — Tomerikoo, Feb 24 '22 at 17:03
@Tomerikoo Still overkill. They already have the index. All they need to do is `tiles[x_turn] = 'X'`. — Kelly Bundy, Feb 24 '22 at 17:04
[https://docs.python.org/3/tutorial/introduction.html#lists](https://docs.python.org/3/tutorial/introduction.html#lists) — wwii, Feb 24 '22 at 17:07
@KellyBundy You're right I didn't realize how simple it was, every time I tried looking it up it never gave me a straight answer and looked complicated. If you leave an answer then I'll check it off as helpful. This was the most helpful and simple response yet. Thank you. — Anthony Periandri, Feb 25 '22 at 16:02
@AnthonyPeriandri Meh, not interesting enough :-P. But feel free to write an answer with it yourself if you want ([that's ok](https://stackoverflow.com/help/self-answer)). Edit: Oh wait, the question is closed, we can't post answers anyway (at least I can't, maybe you as the question's author can, I'm not sure). — Kelly Bundy, Feb 25 '22 at 16:17

score 1 · Answer 1 · answered Feb 24 '22 at 16:25

Something like this?

tiles = list(range(8+1))

while True:
    user_input = input("Enter a number: ")
    if not user_input.isdigit():
        continue
    number = int(user_input)
    if number not in tiles:
        continue
    tiles[number] = 'x'
    print(tiles)

Output:

Enter a number: asdasdasd
Enter a number: 3
[0, 1, 2, 'x', 4, 5, 6, 7, 8]
Enter a number: 4
[0, 1, 2, 'x', 'x', 5, 6, 7, 8]
Enter a number: 0
['x', 1, 2, 'x', 'x', 5, 6, 7, 8]
Enter a number: 0
Enter a number: 10
Enter a number:

This isn't meant to be a complete example - you can only set crosses, not noughts. Also, the program will just keep asking you for input even if you've set all entries to crosses.

score 0 · Answer 2 · edited Feb 24 '22 at 17:05

0

First of all you need to check whose turn is it (x or o) then use this

tiles = [0, 1, 2, 3, 4, 5, 6, 7, 8]
user_input = int(input())
if turn == 'x':
    tiles[tiles.index(user_input)] = 'x'

Of course you should fill in the necessary gaps

edited Feb 24 '22 at 17:05

Tomerikoo

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answered Feb 24 '22 at 16:29

Devil Ishere

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score 0 · Answer 3 · answered Feb 24 '22 at 16:53

In addition to the other answers: move the board's construction inside of the function so that after you replace a tile the board can be reconstructed.

def board():

    play_board = str(tiles[0]) + "|" + str(tiles[1]) + "|" + str(tiles[2])
    play_board_1 = str(tiles[3]) + "|" + str(tiles[4]) + "|" + str(tiles[5])
    play_board_2 = str(tiles[6]) + "|" + str(tiles[7]) + "|" + str(tiles[8])

    print(play_board)
    print(divider)
    print(play_board_1)
    print(divider)
    print(play_board_2)

How do I replace a value in a list corresponding to the user's input?

3 Answers3