Tic-Tac-Toe

Tic-tac-toe with large marks, the game that ends the film. WOPR plays perfectly, so the best you can do is a draw.

Start it

wopr ttt

It is not on LIST GAMES: once logged on, ask WOPR for it by name. It also answers to noughts and crosses, tic-tac-toe and tictactoe.

Click or tap a screenshot to see it larger.

Tic-tac-toe is not on LIST GAMES (wopr --games shows it under ALSO AVAILABLE). Start it with wopr ttt, or ask WOPR for it by name.
At PLEASE LIST NUMBER OF PLAYERS: type 1 to play WOPR. Type 2 for two people taking turns at one keyboard. Type 0 to let WOPR play itself, as at the end of the film.
With one player you are X and move first. WOPR is O and answers each move with a line such as WOPR: 3.
At YOUR MOVE: type a square from 1 to 9. The squares are numbered left to right from the top row. Or type a column letter and a row number, from A1 (top left) to C3 (bottom right). A taken square gets CHOOSE AN EMPTY SQUARE, 1 TO 9.
Three in a row wins. A full board with no line is a draw: WINNER: NONE.

You type	What it does
`1`	at the players prompt, play against WOPR
`2`	at the players prompt, two players take turns
`0`	at the players prompt, WOPR plays itself (the film’s ending)
`5`	take square 5, the centre
`A1`	take the top-left square. Columns are A to C, and rows are 1 to 3
`Esc, Esc`	leave the game and return to WOPR

WOPR never makes a mistake, so a draw is the best result. Before each move, check whether WOPR has two in a row with the third square empty. If it has, block that square.
Open in a corner. The only safe answer is the centre. WOPR always finds it, but a friend playing O in a two-player game often does not.
WOPR picks at random among its best moves, so games differ even though it never loses. With a seed (wopr ttt -s 7), it makes the same choices every time. That helps you study a line of play.
Try 0 players to see what WOPR learns from playing itself.