マルバツゲーム

oxgame.lisp

(defparameter *board*
  (list #\_ #\_ #\_
        #\_ #\_ #\_
        #\_ #\_ #\_))

(defun show-board (board)
  (format t "  012~%")
  (format t "0 ~{~a~}~%" (subseq board 0 3))
  (format t "1 ~{~a~}~%" (subseq board 3 6))
  (format t "2 ~{~a~}~%" (subseq board 6 9)))

;; row * 3 + column
(defun access (row column board)
  (nth (+ column (* 3 row)) board))

(defun check-win (char board)
  (let (result)
    (dolist (i (list 0 3 6) result)
      (or result (setf result (every (lambda (c) (equal c char))
                                     (subseq board i (+ i 3))))))
    (dolist (i (list 0 1 2) result)
      (or result (setf result (every (lambda (c) (equal c char))
                                     (list (access 0 i board)
                                           (access 1 i board)
                                           (access 2 i board))))))
    (or result (setf result (every (lambda (c) (equal c char))
                                   (list (access 0 0 board)
                                         (access 1 1 board)
                                         (access 2 2 board)))))
    (or result (setf result (every (lambda (c) (equal c char))
                                   (list (access 0 2 board)
                                         (access 1 1 board)
                                         (access 2 0 board)))))
    result))

(defun put-char (char row column board)
  (if (equal #\_ (access row column board))
      (setf (nth (+ column (* 3 row)) board) char)
      nil))
(defun finished-p (board)
  (not (some (lambda (c) (equal #\_ c)) board)))

(defun get-input (char)
  (format t "~c turn (row column)> " char)
  (let ((r (read))
        (c (read)))
    (unless (put-char char r c *board*)
      (get-input char))))

(defun game-loop ()
  (show-board *board*)

  (loop
     (get-input #\o)
     (show-board *board*)
     (when (check-win #\o *board*)
       (format t "o win!!~%")
       (return))
     (when (finished-p *board*)
       (format t "draw~%")
       (return))

     (get-input #\x)
     (show-board *board*)
     (when (check-win #\x *board*)
       (format t "x win!!~%")
       (return))
     (when (finished-p *board*)
       (format t "draw~%")
       (return))))

(defun reset-game ()
  (setf *board*
        (list #\_ #\_ #\_
              #\_ #\_ #\_
              #\_ #\_ #\_)))