[Lisp] Tic-Tac-Toe 게임 실습(2)

- 전에 있던 함수에서 컴퓨터가 더 똑똑하게 play하는 함수를 만든다.

[Lisp] Tic-Tac-Toe 게임 실습(1) (tistory.com)

1. squeeze-play와 two-on-one 상황

1) squeeze란 양 대각선에 상대말이 있고 내 말이 중간에 있는 상황을 이야기한다.

여기서 x가 이기 위해서는 대각선에 두면 안되고 변에 둬야한다.

 

2) two-on-on 상황은 대각선에서 연속으로 o(or x)가 두 개 있고 나머지에 x말이 있는 상황을 말한다.

여기서 x가 이기기 위해서는 변에두면 안되고 대각선에 둬야한다.

 

 

2. 함수

* 전역변수 선언

(defvar *Corners* '(1 3 7 9))
(defvar *Sides* '(2 4 6 8))

1) block-squeeze-play

(defun block-squeeze-play (Board)
   "Defending against a squeeze play"
   (sq-and-2 Board *Computer* *Sides* 12 "block squeeze play"))

2) block-two-on-one

(defun block-two-on-one (Board)
   "Defending against a two-on-one attack"
   (sq-and-2 Board *Opponent* *Corners* 12 "block two-on-one"))

3) sq-and-2

(defun sq-and-2 (Board Player Pool V Strategy)
   "squeeze play and two-on-one"
   (when (equal (nth 5 Board) Player)
      (or (sq-helper Board 1 9 V Strategy Pool)
          (sq-helper Board 3 7 V Strategy Pool))))

4) sq-helper

(defun sq-helper (Board C1 C2 Val Strategy Pool)
   "squeeze play and two-on-one"
   (when (equal Val (sum-triplet Board (list C1 5 C2)))
      (let ((Pos (find-empty-position Board (or Pool (list C1 C2)))))
         (and Pos (list Pos Strategy)))))

5) choose-best-move3

(defun choose-best-move3 (Board)
   "3rd version"
   (or (take-center Board)
       (make-three Board)
       (block-opponent-win Board)
       (block-squeeze-play Board)
       (block-two-on-one Board)
       (random-move-strategy Board)))

 

=실행확인용=

;; squeeze play

(setf MyBoard (make-board))

(make-move *Opponent* 1 MyBoard)

(make-move *Computer* 5 MyBoard)

(make-move *Opponent* 9 MyBoard)

(print-board MyBoard)

(block-squeeze-play MyBoard)

(make-move *Computer* 2 MyBoard)

(print-board MyBoard)

 

;; two-on-one

(setf MyBoard (make-board))

(make-move *Opponent* 1 MyBoard)

(make-move *Computer* 9 MyBoard)

(make-move *Opponent* 5 MyBoard)

(print-board MyBoard)

(block-two-on-one MyBoard)

(make-move *Computer* 3 MyBoard)

(print-board MyBoard)