Is it possible to check if multiple string indexes match a variable?

I have a tic tac toe game I made for a milestone project, and currently I have a long if/elif statement that checks all 8 possible win states. I’m trying to simplify it.

board = ['PLACEHOLDER', '-', '-', '-', '-', '-', '-', '-', '-', '-']
tag = X

# Vertical win check
if board[7] == tag and board[4] == tag and board[1] == tag:
    endgame()
elif board[8] == tag and board[5] == tag and board[2] == tag:
    endgame()
elif board[9] == tag and board[6] == tag and board[3] == tag:
    endgame()
# Horizontal win check
elif board[7] == tag and board[8] == tag and board[9] == tag:
    endgame()
elif board[4] == tag and board[5] == tag and board[6] == tag:
    endgame()
elif board[1] == tag and board[2] == tag and board[3] == tag:
    endgame()
# Diagonal win check
elif board[7] == tag and board[5] == tag and board[3] == tag:
    endgame()
elif board[1] == tag and board[5] == tag and board[9] == tag:
    endgame()

Is it possible to check multiples indexes in board at once against the tag string? Something like these two, which I already know don’t work:

if board[7, 4, 1] == tag:
    endgame()

if board[7], [4], [1] == tag:
    endgame()

Or is it even worth trying to simplify?

>Solution :

def endgame():
    print('game end!')


board = ['PLACEHOLDER', '-', '-', '-', '-', '-', '-', '-', '-', '-']
tag = 'X'
idx = [[7, 4, 1], [8, 5, 2], [9, 6, 3], [7, 8, 9], [4, 5, 6], [1, 2, 3], [7, 5, 3], [1, 5, 9]]

for cond in idx:
    if board[cond[0]] == tag and board[cond[1]] == tag and board[cond[2]] == tag:
        endgame()

You could do something like this, which keeps all the win conditions in a list, and iterates over each one, checking if it’s true and ending the game if it’s true.

As khelwood points out, a more clean version of this takes advantage of variable unpacking/destructuring.

for i, j, k in idx:
    if i == tag and j == tag and k == tag:
        endgame()

As Olvin points out, generalizing to dynamic board sizes, with the all() function, we can write this as

for cond in idx:
    if all(board[i] == tag for i in cond):
        endgame()