I've been obsessing with Tic Tac Toe recently, with my post of a bot that plays best-defense against a human player. Along the way I bumped into this thread from 4 years ago, which shows a somewhat golfed and obfuscated script that plays two humans.

I posted my own entry, but wasn't satisfied with it. After some more tinkering and an epiphany or two, I came up with this, measuring in at 159 characters: 

$_="123
456
789
147,258,369,159,357";$p=X;sub d{/.{12}/s;print$&.$p;die$_ for@_}
n:d;$m=<>until$m=~/\d/&&s/$&/$p/g;/$p{3}/?d$p:!/\d/?d"Tie":$p=~y/XO/OX
+/;goto n

[download]
The challenge: Create a script that follows the rules below, in as few characters as possible.

Rules:

  • Standard Tic Tac Toe rules must be followed (e.g., the board is 3x3, each square can be played only once, X and O alternate turns.)
  • A representation of the current game state (the board) must be displayed after each turn. This can take any form that is understandable. (Mine is the squares being numbered 1 through 9 and displayed on a 3x3 console grid)
  • An indicator of who's (X or O) turn it is must be displayed before each turn.
  • A mechanism to accept and validate input must be provided (e.g., it's X's turn until he picks a legal square).
  • A winning move must exit the game and display who won.
  • A "cat" game (tie) must exit and display "Tie" or "Cat" after the last square has been played.

    In reply to (Golf) Tic Tac Toe by delirium

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