lisp/play/mpuz.el

   1 ;;; mpuz.el --- multiplication puzzle for GNU Emacs
   2
   3 ;; Copyright (C) 1990, 2002 Free Software Foundation, Inc.
   4
   5 ;; Author: Philippe Schnoebelen <phs@lsv.ens-cachan.fr>
   6 ;; Overhauled: Daniel Pfeiffer <occitan@esperanto.org>
   7 ;; Keywords: games
   8
   9 ;; This file is part of GNU Emacs.
  10
  11 ;; GNU Emacs is free software; you can redistribute it and/or modify
  12 ;; it under the terms of the GNU General Public License as published by
  13 ;; the Free Software Foundation; either version 2, or (at your option)
  14 ;; any later version.
  15
  16 ;; GNU Emacs is distributed in the hope that it will be useful,
  17 ;; but WITHOUT ANY WARRANTY; without even the implied warranty of
  18 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  19 ;; GNU General Public License for more details.
  20
  21 ;; You should have received a copy of the GNU General Public License
  22 ;; along with GNU Emacs; see the file COPYING.  If not, write to the
  23 ;; Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  24 ;; Boston, MA 02111-1307, USA.
  25
  26 ;;; Commentary:
  27
  28 ;; `M-x mpuz' generates a random multiplication puzzle.  This is a
  29 ;; multiplication example in which each digit has been consistently replaced
  30 ;; with some letter.  Your job is to reconstruct the original digits.  Type
  31 ;; `?' while the mode is active for detailed help.
  32
  33 ;;; Code:
  34
  35 (defgroup mpuz nil
  36   "Multiplication puzzle."
  37   :prefix "mpuz-"
  38   :group 'games)
  39
  40 (random t)                              ; randomize
  41
  42 (defcustom mpuz-silent 'error
  43   "*Set this to `nil' if you want dings on inputs.
  44 `t' means never ding, and `error' means only ding on wrong input."
  45   :type '(choice (const :tag "No" nil)
  46                  (const :tag "Yes" t)
  47                  (const :tag "If correct" error))
  48   :group 'mpuz)
  49
  50 (defcustom mpuz-solve-when-trivial t
  51   "*Solve any row that can be trivially calculated from what you've found."
  52   :type 'boolean
  53   :group 'mpuz)
  54
  55 (defcustom mpuz-allow-double-multiplicator nil
  56   "*Allow 2nd factors like 33 or 77."
  57   :type 'boolean
  58   :group 'mpuz)
  59
  60 (defface mpuz-unsolved-face
  61   '((((class color)) (:foreground "red1" :bold t))
  62     (t (:bold t)))
  63   "*Face to use for letters to be solved."
  64   :group 'mpuz)
  65
  66 (defface mpuz-solved-face
  67   '((((class color)) (:foreground "green1" :bold t))
  68     (t (:bold t)))
  69   "*Face to use for solved digits."
  70   :group 'mpuz)
  71
  72 (defface mpuz-trivial-face
  73   '((((class color)) (:foreground "blue" :bold t))
  74     (t (:bold t)))
  75   "*Face to use for trivial digits solved for you."
  76   :group 'mpuz)
  77
  78 (defface mpuz-text-face
  79   '((t (:inherit variable-pitch)))
  80   "*Face to use for text on right."
  81   :group 'mpuz)
  82
  83 \f
  84 ;; Mpuz mode and keymaps
  85 ;;----------------------
  86 (defcustom mpuz-mode-hook nil
  87   "Hook to run upon entry to mpuz."
  88   :type 'hook
  89   :group 'mpuz)
  90
  91 (defvar mpuz-mode-map nil
  92   "Local keymap to use in Mult Puzzle.")
  93
  94 (if mpuz-mode-map nil
  95   (setq mpuz-mode-map (make-sparse-keymap))
  96   (define-key mpuz-mode-map "a" 'mpuz-try-letter)
  97   (define-key mpuz-mode-map "b" 'mpuz-try-letter)
  98   (define-key mpuz-mode-map "c" 'mpuz-try-letter)
  99   (define-key mpuz-mode-map "d" 'mpuz-try-letter)
 100   (define-key mpuz-mode-map "e" 'mpuz-try-letter)
 101   (define-key mpuz-mode-map "f" 'mpuz-try-letter)
 102   (define-key mpuz-mode-map "g" 'mpuz-try-letter)
 103   (define-key mpuz-mode-map "h" 'mpuz-try-letter)
 104   (define-key mpuz-mode-map "i" 'mpuz-try-letter)
 105   (define-key mpuz-mode-map "j" 'mpuz-try-letter)
 106   (define-key mpuz-mode-map "A" 'mpuz-try-letter)
 107   (define-key mpuz-mode-map "B" 'mpuz-try-letter)
 108   (define-key mpuz-mode-map "C" 'mpuz-try-letter)
 109   (define-key mpuz-mode-map "D" 'mpuz-try-letter)
 110   (define-key mpuz-mode-map "E" 'mpuz-try-letter)
 111   (define-key mpuz-mode-map "F" 'mpuz-try-letter)
 112   (define-key mpuz-mode-map "G" 'mpuz-try-letter)
 113   (define-key mpuz-mode-map "H" 'mpuz-try-letter)
 114   (define-key mpuz-mode-map "I" 'mpuz-try-letter)
 115   (define-key mpuz-mode-map "J" 'mpuz-try-letter)
 116   (define-key mpuz-mode-map "\C-g" 'mpuz-offer-abort)
 117   (define-key mpuz-mode-map "?" 'describe-mode))
 118
 119 (defun mpuz-mode ()
 120   "Multiplication puzzle mode.
 121
 122 You have to guess which letters stand for which digits in the
 123 multiplication displayed inside the `*Mult Puzzle*' buffer.
 124
 125 You may enter a guess for a letter's value by typing first the letter,
 126 then the digit.  Thus, to guess that A=3, type `A 3'.
 127
 128 To leave the game to do other editing work, just switch buffers.
 129 Then you may resume the game with M-x mpuz.
 130 You may abort a game by typing \\<mpuz-mode-map>\\[mpuz-offer-abort]."
 131   (interactive)
 132   (setq major-mode 'mpuz-mode
 133         mode-name  "Mult Puzzle"
 134         tab-width 30)
 135   (use-local-map mpuz-mode-map)
 136   (run-hooks 'mpuz-mode-hook))
 137
 138 \f
 139 ;; Some variables for statistics
 140 ;;------------------------------
 141 (defvar mpuz-nb-errors 0
 142   "Number of errors made in current game.")
 143
 144 (defvar mpuz-nb-completed-games 0
 145   "Number of games completed.")
 146
 147 (defvar mpuz-nb-cumulated-errors 0
 148   "Number of errors made in previous games.")
 149
 150
 151 ;; Some variables for game tracking
 152 ;;---------------------------------
 153 (defvar mpuz-in-progress nil
 154   "True if a game is currently in progress.")
 155
 156 (defvar mpuz-found-digits (make-bool-vector 10 nil)
 157   "A vector recording which digits have been decrypted.")
 158
 159 (defvar mpuz-trivial-digits (make-bool-vector 10 nil)
 160   "A vector recording which digits have been solved for you.")
 161
 162 (defmacro mpuz-digit-solved-p (digit)
 163   `(or (aref mpuz-found-digits ,digit)
 164        (aref mpuz-trivial-digits ,digit)))
 165
 166
 167 ;; A puzzle uses a permutation of [0..9] into itself.
 168 ;; We use both the permutation and its inverse.
 169 ;;---------------------------------------------------
 170 (defvar mpuz-digit-to-letter (make-vector 10 0)
 171   "A permutation from [0..9] to [0..9].")
 172
 173 (defvar mpuz-letter-to-digit (make-vector 10 0)
 174   "The inverse of mpuz-digit-to-letter.")
 175
 176 (defmacro mpuz-to-digit (letter)
 177   (list 'aref 'mpuz-letter-to-digit letter))
 178
 179 (defmacro mpuz-to-letter (digit)
 180   (list 'aref 'mpuz-digit-to-letter digit))
 181
 182 (defun mpuz-build-random-perm ()
 183   "Initialize puzzle coding with a random permutation."
 184   (let ((letters (list 0 1 2 3 4 5 6 7 8 9)) ; new cons cells, because of delq
 185         (index 10)
 186         elem)
 187     (while letters
 188       (setq elem    (nth (random index) letters)
 189             letters (delq elem letters)
 190             index   (1- index))
 191       (aset mpuz-digit-to-letter index elem)
 192       (aset mpuz-letter-to-digit elem index))))
 193
 194
 195 ;; A puzzle also uses a board displaying a multiplication.
 196 ;; Every digit appears in the board, crypted or not.
 197 ;;------------------------------------------------------
 198 (defvar mpuz-board (make-vector 10 nil)
 199   "The board associates to any digit the list of squares where it appears.")
 200
 201 (defun mpuz-put-number-on-board (number row &rest l)
 202   "Put (last digit of) NUMBER on ROW and COLUMNS of the puzzle board."
 203   (let (digit)
 204     (while l
 205       (setq digit (% number 10)
 206             number (/ number 10))
 207       (aset mpuz-board digit `((,row . ,(car l)) ,@(aref mpuz-board digit)))
 208       (setq l (cdr l)))))
 209
 210 (defun mpuz-check-all-solved (&optional row col)
 211   "Check whether all digits have been solved. Return t if yes."
 212   (catch 'solved
 213     (let (A B1 B2 C D E squares)
 214       (and mpuz-solve-when-trivial
 215            (not row)
 216            (while
 217                (cond ((or (and (setq B1 (or B1 (mpuz-check-all-solved 4 7))
 218                                      B2 (or B2 (mpuz-check-all-solved 4 9))
 219                                      E (or E (mpuz-check-all-solved 10))
 220                                      A (or A (mpuz-check-all-solved 2)))
 221                                B1 B2)
 222                           (and E (or A (and B1 B2))))
 223                       (mpuz-solve)
 224                       (mpuz-paint-board)
 225                       (throw 'solved t))
 226                      ((and (setq D (or D (mpuz-check-all-solved 8))
 227                                  C (or C (mpuz-check-all-solved 6)))
 228                            D (not E))
 229                       (mpuz-solve 10))
 230                      ((and E (not (eq C D)))
 231                       (mpuz-solve (if D 6 8)))
 232                      ((and A (not (eq B2 C)))
 233                       (mpuz-solve (if C 4 6) (if C 9)))
 234                      ((and A (not (eq B1 D)))
 235                       (mpuz-solve (if D 4 8) (if D 7)))
 236                      ((and (not A) (or (and B2 C) (and B1 D)))
 237                       (mpuz-solve 2)))))
 238       (mpuz-paint-board)
 239       (mapc (lambda (digit)
 240               (and (not (mpuz-digit-solved-p digit)) ; unsolved
 241                    (setq squares (aref mpuz-board digit))
 242                    (if row
 243                        (if col
 244                            (member (cons row col) squares)
 245                          (assq row squares))
 246                      squares) ; and appearing in the puzzle!
 247                    (throw 'solved nil)))
 248             [0 1 2 3 4 5 6 7 8 9]))
 249     t))
 250
 251
 252 ;; To build a puzzle, we take two random numbers and multiply them.
 253 ;; We also take a random permutation for encryption.
 254 ;; The random numbers are only use to see which digit appears in which square
 255 ;; of the board. Everything is stored in individual squares.
 256 ;;---------------------------------------------------------------------------
 257 (defun mpuz-random-puzzle ()
 258   "Draw random values to be multiplied in a puzzle."
 259   (mpuz-build-random-perm)
 260   (fillarray mpuz-board nil)            ; erase the board
 261   ;; A,B,C,D & E, are the five rows of our multiplication.
 262   ;; Choose random values, discarding cases with leading zeros in C or D.
 263   (let* ((A (+ 112 (random 888)))
 264          (min (1+ (/ 1000 A)))
 265          (B1 (+ min (random (- 10 min))))
 266          B2 C D E)
 267     (while (if (= B1 (setq B2 (+ min (random (- 10 min)))))
 268                (not mpuz-allow-double-multiplicator)))
 269     (setq C (* A B2)
 270           D (* A B1)
 271           E (+ C (* D 10)))
 272     ;; Individual digits are now put on their respective squares.
 273     ;; [NB: A square is a pair (row . column) of the screen.]
 274     (mpuz-put-number-on-board A 2                9 7 5)
 275     (mpuz-put-number-on-board (+ (* B1 10) B2) 4 9 7)
 276     (mpuz-put-number-on-board C 6                9 7 5 3)
 277     (mpuz-put-number-on-board D 8                  7 5 3 1)
 278     (mpuz-put-number-on-board E 10               9 7 5 3 1)))
 279 \f
 280 ;; Display
 281 ;;--------
 282 (defconst mpuz-framework
 283   "
 284      . . .
 285         Number of errors (this game):   0
 286     x  . .
 287    -------
 288    . . . .
 289         Number of completed games:      0
 290  . . . .
 291  ---------      Average number of errors:       0.00
 292  . . . . ."
 293   "The general picture of the puzzle screen, as a string.")
 294
 295 (defun mpuz-create-buffer ()
 296   "Create (or recreate) the puzzle buffer. Return it."
 297   (let ((buf (get-buffer-create "*Mult Puzzle*"))
 298         (face '(face mpuz-text-face))
 299         buffer-read-only)
 300     (save-excursion
 301       (set-buffer buf)
 302       (erase-buffer)
 303       (insert mpuz-framework)
 304       (set-text-properties 13 42 face)
 305       (set-text-properties 79 105 face)
 306       (set-text-properties 128 153 face)
 307       (mpuz-paint-board)
 308       (mpuz-paint-errors)
 309       (mpuz-paint-statistics))
 310     buf))
 311
 312 (defun mpuz-paint-number (n &optional eol words)
 313   (end-of-line eol)
 314   (let (buffer-read-only)
 315     (delete-region (point)
 316                    (progn (backward-word (or words 1)) (point)))
 317     (insert n)))
 318
 319 (defun mpuz-paint-errors ()
 320   "Paint error count on the puzzle screen."
 321   (mpuz-switch-to-window)
 322   (goto-line 3)
 323   (mpuz-paint-number (prin1-to-string mpuz-nb-errors)))
 324
 325 (defun mpuz-paint-statistics ()
 326   "Paint statistics about previous games on the puzzle screen."
 327   (goto-line 7)
 328   (mpuz-paint-number (prin1-to-string mpuz-nb-completed-games))
 329   (mpuz-paint-number
 330    (format "%.2f"
 331            (if (zerop mpuz-nb-completed-games)
 332                0
 333              (/ (+ 0.0 mpuz-nb-cumulated-errors)
 334                 mpuz-nb-completed-games)))
 335    3 2))
 336
 337 (defun mpuz-paint-board ()
 338   "Paint board situation on the puzzle screen."
 339   (mpuz-switch-to-window)
 340   (mapc 'mpuz-paint-digit [0 1 2 3 4 5 6 7 8 9])
 341   (goto-char (point-min)))
 342
 343 (defun mpuz-paint-digit (digit)
 344   "Paint all occurrences of DIGIT on the puzzle board."
 345   (let ((char (if (mpuz-digit-solved-p digit)
 346                   (+ digit ?0)
 347                 (+ (mpuz-to-letter digit) ?A)))
 348         (face `(face
 349                 ,(cond ((aref mpuz-trivial-digits digit) 'mpuz-trivial-face)
 350                        ((aref mpuz-found-digits digit) 'mpuz-solved-face)
 351                        ('mpuz-unsolved-face))))
 352         buffer-read-only)
 353     (mapc (lambda (square)
 354             (goto-line (car square))    ; line before column!
 355             (move-to-column (cdr square))
 356             (insert char)
 357             (set-text-properties (1- (point)) (point) face)
 358             (delete-char 1))
 359           (aref mpuz-board digit))))
 360
 361 (defun mpuz-get-buffer ()
 362   "Get the puzzle buffer if it exists."
 363   (get-buffer "*Mult Puzzle*"))
 364
 365 (defun mpuz-switch-to-window ()
 366   "Find or create the Mult-Puzzle buffer, and display it."
 367   (let ((buf (mpuz-get-buffer)))
 368     (or buf (setq buf (mpuz-create-buffer)))
 369     (switch-to-buffer buf)
 370     (or buffer-read-only (toggle-read-only))
 371     (mpuz-mode)))
 372
 373 \f
 374 ;; Game control
 375 ;;-------------
 376 (defun mpuz-start-new-game ()
 377   "Start a new puzzle."
 378   (message "Here we go...")
 379   (setq mpuz-nb-errors 0
 380         mpuz-in-progress t)
 381   (fillarray mpuz-found-digits nil)     ; initialize mpuz-found-digits
 382   (fillarray mpuz-trivial-digits nil)
 383   (mpuz-random-puzzle)
 384   (mpuz-switch-to-window)
 385   (mpuz-paint-board)
 386   (mpuz-paint-errors)
 387   (mpuz-ask-for-try))
 388
 389 ;;;###autoload
 390 (defun mpuz ()
 391   "Multiplication puzzle with GNU Emacs."
 392   ;; Main entry point
 393   (interactive)
 394   (mpuz-switch-to-window)
 395   (if mpuz-in-progress
 396       (mpuz-offer-abort)
 397     (mpuz-start-new-game)))
 398
 399 (defun mpuz-offer-abort ()
 400   "Ask if user wants to abort current puzzle."
 401   (interactive)
 402   (if (y-or-n-p "Abort game ")
 403       (let ((buf (mpuz-get-buffer)))
 404         (message "Mult Puzzle aborted.")
 405         (setq mpuz-in-progress nil
 406               mpuz-nb-errors 0)
 407         (fillarray mpuz-board nil)
 408         (if buf (kill-buffer buf)))
 409     (mpuz-ask-for-try)))
 410
 411 (defun mpuz-ask-for-try ()
 412   "Ask for user proposal in puzzle."
 413   (message "Your try?"))
 414
 415 (defun mpuz-ding (error)
 416   "Dings, unless global variable `mpuz-silent' forbids it."
 417   (cond ((eq mpuz-silent t))
 418         ((not mpuz-silent) (ding t))
 419         (error (ding t))))
 420
 421 (defun mpuz-try-letter ()
 422   "Propose a digit for a letter in puzzle."
 423   (interactive)
 424   (if mpuz-in-progress
 425       (let (letter-char digit digit-char message)
 426         (setq letter-char (upcase last-command-char)
 427               digit (mpuz-to-digit (- letter-char ?A)))
 428         (cond ((mpuz-digit-solved-p digit)
 429                (message "%c already solved." letter-char)
 430                (mpuz-ding t))
 431               ((null (aref mpuz-board digit))
 432                (message "%c does not appear." letter-char)
 433                (mpuz-ding t))
 434               ((progn (message "%c = " letter-char)
 435                       ;; <char> has been entered.
 436                       ;; Print "<char> =" and
 437                       ;; read <num> or = <num>
 438                       (setq digit-char (read-char))
 439                       (if (eq digit-char ?=)
 440                           (setq digit-char (read-char)))
 441                       (or (> digit-char ?9) (< digit-char ?0))) ; bad input
 442                (message "%c = %c" letter-char digit-char)
 443                (mpuz-ding t))
 444               (t
 445                (mpuz-try-proposal letter-char digit-char))))
 446     (if (y-or-n-p "Start a new game ")
 447         (mpuz-start-new-game)
 448       (message "OK. I won't."))))
 449
 450 (defun mpuz-try-proposal (letter-char digit-char)
 451   "Propose LETTER-CHAR as code for DIGIT-CHAR."
 452   (let* ((letter (- letter-char ?A))
 453          (digit (- digit-char ?0))
 454          (correct-digit (mpuz-to-digit letter))
 455          (game mpuz-nb-completed-games))
 456     (cond ((mpuz-digit-solved-p correct-digit)
 457            (message "%c has already been found." (+ correct-digit ?0)))
 458           ((mpuz-digit-solved-p digit)
 459            (message "%c has already been placed." digit-char))
 460           ((= digit correct-digit)
 461            (message "%c = %c correct!" letter-char digit-char)
 462            (mpuz-ding nil)
 463            (aset mpuz-found-digits digit t)     ; Mark digit as solved
 464            (and (mpuz-check-all-solved)
 465                 (mpuz-close-game)))
 466           (t ;;; incorrect guess
 467            (message "%c = %c incorrect!" letter-char digit-char)
 468            (mpuz-ding t)
 469            (setq mpuz-nb-errors (1+ mpuz-nb-errors))
 470            (mpuz-paint-errors)))))
 471
 472 (defun mpuz-close-game ()
 473   "Housecleaning when puzzle has been solved."
 474   (setq mpuz-in-progress nil
 475         mpuz-nb-cumulated-errors (+ mpuz-nb-cumulated-errors mpuz-nb-errors)
 476         mpuz-nb-completed-games (1+ mpuz-nb-completed-games))
 477   (mpuz-paint-statistics)
 478   (let ((message (format "Puzzle solved with %d error%s. That's %s"
 479                          mpuz-nb-errors
 480                          (if (= mpuz-nb-errors 1) "" "s")
 481                          (cond ((= mpuz-nb-errors 0)    "perfect!")
 482                                ((= mpuz-nb-errors 1)    "very good!")
 483                                ((= mpuz-nb-errors 2)    "good.")
 484                                ((= mpuz-nb-errors 3)    "not bad.")
 485                                ((= mpuz-nb-errors 4)    "not too bad...")
 486                                ((< mpuz-nb-errors 10)   "bad!")
 487                                ((< mpuz-nb-errors 15)   "awful.")
 488                                (t                       "not serious.")))))
 489     (message message)
 490     (sit-for 4)
 491     (if (y-or-n-p (concat message "  Start a new game "))
 492         (mpuz-start-new-game)
 493       (message "Good Bye!"))))
 494
 495 (defun mpuz-solve (&optional row col)
 496   "Find solution for autosolving."
 497   (mapc (lambda (digit)
 498           (or (mpuz-digit-solved-p digit)
 499               (if row
 500                   (not (if col
 501                            (member (cons row col) (aref mpuz-board digit))
 502                          (assq row (aref mpuz-board digit)))))
 503               (aset mpuz-trivial-digits digit t)))
 504         [0 1 2 3 4 5 6 7 8 9])
 505   t)
 506
 507 (defun mpuz-show-solution (row)
 508   "Display solution for debugging purposes."
 509   (interactive "P")
 510   (mpuz-switch-to-window)
 511   (mpuz-solve (if row (* 2 (prefix-numeric-value row))))
 512   (mpuz-paint-board)
 513   (if (mpuz-check-all-solved)
 514       (mpuz-close-game)))
 515
 516 (provide 'mpuz)
 517
 518 ;;; mpuz.el ends here