使用lisp语言写一个俄罗斯方块程序

以下是一个简单的俄罗斯方块程序，使用Lisp编写：

;; 定义方块形状
(defstruct block
  (type nil)
  (shape nil)
  (x 0)
  (y 0))

(defvar *shapes*
  '((1 1 1 1)          ; I
    (1 0 0 0           ; J
     1 1 1 0)
    (0 0 1 0           ; L
     1 1 1 0)
    (1 1              ; O
     1 1)
    (0 1 1 0           ; S
     1 1 0 0)
    (1 1 0 0           ; T
     0 1 1 0)
    (0 1 1 0           ; Z
     0 0 1 1)))

;; 创建一个新的方块
(defun new-block ()
  (let ((type (random (length *shapes*)))
        (shape (elt *shapes* (random (length *shapes*)))))
    (make-block :type type :shape shape :x 5 :y 0)))

(defvar *board* (make-array '(20 10) :initial-element nil))
(defvar *current-block* nil)

;; 检查方块是否可放置
(defun block-can-move-p (block dx dy)
  (loop for i from 0 below 4
        for row = (elt (block-shape block) i)
        for x = (+ (block-x block) (floor i 2))
        for y from (1- (block-y block)) below (+ (block-y block) 1)
        when (and (< (+ x dx) 0) (or (> (+ x dx) 9) (aref *board* y (+ x dx))))
             (return nil)
        when (and (> (+ x dx) 9) (or (< (+ x dx) 0) (aref *board* y (- (+ x dx) 10))))
             (return nil)
        when (and (>= (+ y dy) 20) (aref *board* (- (+ y dy) 20) x))
             (return nil)
        when (and (< (+ y dy) 0) (aref *board* y x))
             (return nil))
  t)

;; 将方块放置在棋盘上
(defun place-block (block)
  (loop for i from 0 below 4
        for row = (elt (block-shape block) i)
        for x = (+ (block-x block) (floor i 2))
        for y from (1- (block-y block)) below (+ (block-y block) 1)
        do (when (and (>= y 0) (< y 20) (>= x 0) (< x 10) row)
             (setf (aref *board* y x) (block-type block)))))

;; 从棋盘上移除方块
(defun remove-block (block)
  (loop for i from 0 below 4
        for row = (elt (block-shape block) i)
        for x = (+ (block-x block) (floor i 2))
        for y from (1- (block-y block)) below (+ (block-y block) 1)
        do (when (and (>= y 0) (< y 20) (>= x 0) (< x 10) row)
             (setf (aref *board* y x) nil))))

;; 将方块向左移动
(defun move-left ()
  (when (block-can-move-p *current-block* -1 0)
    (remove-block *current-block*)
    (setf (block-x *current-block*) (1- (block-x *current-block*)))
    (place-block *current-block*)))

;; 将方块向右移动
(defun move-right ()
  (when (block-can-move-p *current-block* 1 0)
    (remove-block *current-block*)
    (setf (block-x *current-block*) (1+ (block-x *current-block*)))
    (place-block *current-block*)))

;; 将方块旋转
(defun rotate ()
  (let ((shape (block-shape *current-block*))
        (new-shape nil))
    (dotimes (i 4)
      (let ((row (elt shape i)))
        (dotimes (j 4)
          (setf (elt new-shape (+ 3 j (* -4 i)))
                (elt row j)))))
    (setf (block-shape *current-block*) new-shape)
    (when (not (block-can-move-p *current-block* 0 0))
      (setf (block-shape *current-block*) shape))
    (remove-block *current-block*)
    (place-block *current-block*)))

;; 让方块落下
(defun tick ()
  (when (block-can-move-p *current-block* 0 1)
    (remove-block *current-block*)
    (setf (block-y *current-block*) (1+ (block-y *current-block*)))
    (place-block *current-block*))
  (when (not (block-can-move-p *current-block* 0 1))
    (setf *current-block* (new-block))))

这个程序使用一个20x10的二维数组表示棋盘，每个方格可以为空，或者被一个方块占据。每个方块由一个类型、一个形状和一个坐标表示。程序可以检查方块是否可以向左或向右移动，是否可以旋转，是否可以落下。程序还定义了一个新的方块生成函数，以及将方块放置在棋盘上和从棋盘上移除方块的函数。