Python - How can I find if an item exists in multidimensional array?

Question

I've tried a few approaches, none of which seem to work for me.

board = [[0,0,0,0],[0,0,0,0]]

if not 0 in board:
     # the board is "full"

I then tried:

if not 0 in board[0] or not 0 in board[1]:
    # the board is "full"

None of these approaches worked, though the second one generally let the array fill up more. (I wrote code to fill up the array randomly).

Answer 1

You need to iterate over all the indices of your list to see if an element is a value in one of the nested lists. You can simply iterate over the inner lists and check for the presence of your element, e.g.:

if not any(0 in x for x in board):
    pass  # the board is full

Using any() will serve as a short-stop whenever it encounters an element with a 0 in it so you don't need to iterate over the rest.