Why is this if statement being triggered when the list does not contain the conditions the if statem-CodePudding

Why is the first if statement being triggered and not the elif statement after it?

player_moves = [1, 3, 4]
computer_moves = [5, 2]
if 4 and 5 in computer_moves and 6 not in player_moves:
    computer_moves.append(6)
    print("Computer chooses "   str(computer_moves[-1]))
elif 2 and 5 in computer_moves and 8 not in player_moves:
    computer_moves.append(8)
    print("Computer chooses "   str(computer_moves[-1]))

CodePudding user response：

if 4 and 5 in computer_moves and 6 not in player_moves: is same as

if 4 and (5 in computer_moves) and (6 not in player_moves):,

change to

if 4 in computer_moves and 5 in computer_moves and 6 not in player_moves:

True and True and True

Same problem in the elif.

elif 2 and 5 in computer_moves and 8 not in player_moves: same as

elif 2 and (5 in computer_moves) and (8 not in player_moves):

CodePudding user response：

Ok so:

In your IF statements you have the conditions (4 and 5) and (2 and 5). Your mistake is quite common. Instead of your code checking whether BOTH 4 and 5 are in the list computer_moves, it actually evaluates the boolean expression (4 and 5) which returns True, and then checks if True is in computer_moves.

You need to change your IF statements to:

if (4 in computer_moves) and (5 in computer_moves) and (6 not in computer_moves):