release/src/router/libncurses/test/knight.c

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  28 /*
  29  * Knight's Tour - a brain game
  30  *
  31  * The original of this game was anonymous.  It had an unbelievably bogus
  32  * interface, you actually had to enter square coordinates!  Redesign by
  33  * Eric S. Raymond <esr@snark.thyrsus.com> July 22 1995.  Mouse support
  34  * added September 20th 1995.
  35  *
  36  * $Id: knight.c,v 1.36 2013/02/16 19:53:08 tom Exp $
  37  */
  38
  39 #include <test.priv.h>
  40
  41 /* board size */
  42 #define BDEPTH  8
  43 #define BWIDTH  8
  44
  45 /* where to start the instructions */
  46 #define INSTRY  2
  47 #define INSTRX  35
  48
  49 /* corner of board */
  50 #define BOARDY  2
  51 #define BOARDX  0
  52
  53 /* notification line */
  54 #define NOTIFYY 21
  55
  56 /* virtual color values */
  57 #define TRAIL_COLOR     1
  58 #define PLUS_COLOR      2
  59 #define MINUS_COLOR     3
  60
  61 #define CX(x)           (2 + 4 * (x))
  62 #define CY(y)           (1 + 2 * (y))
  63 #define cellmove(y, x)  wmove(boardwin, CY(y), CX(x))
  64 #define CXINV(x)        (((x) - 1) / 4)
  65 #define CYINV(y)        (((y) - 2) / 2)
  66
  67 typedef struct {
  68     short x, y;
  69 } cell;
  70
  71 static WINDOW *boardwin;        /* the board window */
  72 static WINDOW *helpwin;         /* the help window */
  73 static WINDOW *msgwin;          /* the message window */
  74 static cell history[BDEPTH * BWIDTH + 1];       /* choice history */
  75 static chtype minus = '-';      /* possible-move character */
  76 static chtype oldch;
  77 static chtype plus = '+';       /* cursor hot-spot character */
  78 static chtype trail = '#';      /* trail character */
  79 static int movecount;           /* count of moves so far */
  80 static int trialcount;          /* count of trials so far */
  81 static short board[BDEPTH][BWIDTH];     /* the squares */
  82 /* *INDENT-OFF* */
  83 static const struct {
  84     int y;
  85     int x;
  86 } offsets[] = {
  87     {  2,  1 },
  88     {  1,  2 },
  89     { -1,  2 },
  90     { -2,  1 },
  91     { -2, -1 },
  92     { -1, -2 },
  93     {  1, -2 },
  94     {  2, -1 },
  95 };
  96 /* *INDENT-ON* */
  97
  98 static void
  99 init_program(void)
 100 {
 101     setlocale(LC_ALL, "");
 102
 103     srand((unsigned) getpid());
 104     initscr();
 105     cbreak();                   /* immediate char return */
 106     noecho();                   /* no immediate echo */
 107     boardwin = newwin(BDEPTH * 2 + 1, BWIDTH * 4 + 1, BOARDY, BOARDX);
 108     helpwin = newwin(0, 0, INSTRY, INSTRX);
 109     msgwin = newwin(1, INSTRX - 1, NOTIFYY, 0);
 110     scrollok(msgwin, TRUE);
 111     keypad(boardwin, TRUE);
 112
 113     if (has_colors()) {
 114         int bg = COLOR_BLACK;
 115
 116         start_color();
 117 #if HAVE_USE_DEFAULT_COLORS
 118         if (use_default_colors() == OK)
 119             bg = -1;
 120 #endif
 121
 122         (void) init_pair(TRAIL_COLOR, (short) COLOR_CYAN, (short) bg);
 123         (void) init_pair(PLUS_COLOR, (short) COLOR_RED, (short) bg);
 124         (void) init_pair(MINUS_COLOR, (short) COLOR_GREEN, (short) bg);
 125
 126         trail |= (chtype) COLOR_PAIR(TRAIL_COLOR);
 127         plus |= (chtype) COLOR_PAIR(PLUS_COLOR);
 128         minus |= (chtype) COLOR_PAIR(MINUS_COLOR);
 129     }
 130 #ifdef NCURSES_MOUSE_VERSION
 131     (void) mousemask(BUTTON1_CLICKED, (mmask_t *) NULL);
 132 #endif /* NCURSES_MOUSE_VERSION */
 133 #if defined(PDCURSES)
 134     mouse_set(BUTTON1_RELEASED);
 135 #endif
 136
 137     oldch = minus;
 138 }
 139
 140 static void
 141 help1(void)
 142 /* game explanation -- initial help screen */
 143 {
 144     (void) waddstr(helpwin, "Knight's move is a solitaire puzzle.  Your\n");
 145     (void) waddstr(helpwin, "objective is to visit each square of the  \n");
 146     (void) waddstr(helpwin, "chessboard exactly once by making knight's\n");
 147     (void) waddstr(helpwin, "moves (one square right or left followed  \n");
 148     (void) waddstr(helpwin, "by two squares up or down, or two squares \n");
 149     (void) waddstr(helpwin, "right or left followed by one square up or\n");
 150     (void) waddstr(helpwin, "down).  You may start anywhere.\n\n");
 151
 152     (void) waddstr(helpwin, "Use arrow keys to move the cursor around.\n");
 153     (void) waddstr(helpwin, "When you want to move your knight to the \n");
 154     (void) waddstr(helpwin, "cursor location, press <space> or Enter.\n");
 155     (void) waddstr(helpwin, "Illegal moves will be rejected with an  \n");
 156     (void) waddstr(helpwin, "audible beep.\n\n");
 157     (void) waddstr(helpwin, "The program will detect if you solve the\n");
 158     (void) waddstr(helpwin, "puzzle; also inform you when you run out\n");
 159     (void) waddstr(helpwin, "of legal moves.\n\n");
 160
 161     MvWAddStr(helpwin, NOTIFYY - INSTRY, 0,
 162               "Press `?' to go to keystroke help.");
 163 }
 164
 165 static void
 166 help2(void)
 167 /* keystroke help screen */
 168 {
 169     (void) waddstr(helpwin, "Possible moves are shown with `-'.\n\n");
 170
 171     (void) waddstr(helpwin, "You can move around with the arrow keys or\n");
 172     (void) waddstr(helpwin, "with the rogue/hack movement keys.  Other\n");
 173     (void) waddstr(helpwin, "commands allow you to undo moves or redraw.\n");
 174     (void) waddstr(helpwin, "Your mouse may work; try left-button to\n");
 175     (void) waddstr(helpwin, "move to the square under the pointer.\n\n");
 176
 177     (void) waddstr(helpwin, "x,q -- exit             y k u    7 8 9\n");
 178     (void) waddstr(helpwin, "r -- redraw screen       \\|/      \\|/ \n");
 179     (void) waddstr(helpwin, "bksp -- undo move       h-+-l    4-+-6\n");
 180     (void) waddstr(helpwin, "a -- autojump            /|\\      /|\\ \n");
 181     (void) waddstr(helpwin, "                        b j n    1 2 3\n");
 182
 183     (void) waddstr(helpwin, "\nYou can place your knight on the selected\n");
 184     (void) waddstr(helpwin, "square with spacebar, Enter, or the keypad\n");
 185     (void) waddstr(helpwin, "center key.  Use F/B to review the path.\n");
 186
 187     MvWAddStr(helpwin, NOTIFYY - INSTRY, 0,
 188               "Press `?' to go to game explanation");
 189 }
 190
 191 static void
 192 show_help(bool * keyhelp)
 193 {
 194     werase(helpwin);
 195     if (*keyhelp) {
 196         help1();
 197         *keyhelp = FALSE;
 198     } else {
 199         help2();
 200         *keyhelp = TRUE;
 201     }
 202     wrefresh(helpwin);
 203 }
 204
 205 static bool
 206 chksqr(int r1, int c1)
 207 {
 208     if ((r1 < 0) || (r1 > BDEPTH - 1))
 209         return (FALSE);
 210     if ((c1 < 0) || (c1 > BWIDTH - 1))
 211         return (FALSE);
 212     return ((!board[r1][c1]) ? TRUE : FALSE);
 213 }
 214
 215 static bool
 216 chkmoves(int rw, int col)
 217 /* check to see if valid moves are available */
 218 {
 219     unsigned n;
 220
 221     for (n = 0; n < SIZEOF(offsets); n++)
 222         if (chksqr(rw + offsets[n].y, col + offsets[n].x))
 223             return (TRUE);
 224     return (FALSE);
 225 }
 226
 227 static void
 228 dosquares(void)
 229 {
 230     int i, j;
 231
 232     MvAddStr(0, 20, "KNIGHT'S MOVE -- a logical solitaire");
 233
 234     move(BOARDY, BOARDX);
 235     waddch(boardwin, ACS_ULCORNER);
 236     for (j = 0; j < 7; j++) {
 237         waddch(boardwin, ACS_HLINE);
 238         waddch(boardwin, ACS_HLINE);
 239         waddch(boardwin, ACS_HLINE);
 240         waddch(boardwin, ACS_TTEE);
 241     }
 242     waddch(boardwin, ACS_HLINE);
 243     waddch(boardwin, ACS_HLINE);
 244     waddch(boardwin, ACS_HLINE);
 245     waddch(boardwin, ACS_URCORNER);
 246
 247     for (i = 1; i < BDEPTH; i++) {
 248         move(BOARDY + i * 2 - 1, BOARDX);
 249         waddch(boardwin, ACS_VLINE);
 250         for (j = 0; j < BWIDTH; j++) {
 251             waddch(boardwin, ' ');
 252             waddch(boardwin, ' ');
 253             waddch(boardwin, ' ');
 254             waddch(boardwin, ACS_VLINE);
 255         }
 256         move(BOARDY + i * 2, BOARDX);
 257         waddch(boardwin, ACS_LTEE);
 258         for (j = 0; j < BWIDTH - 1; j++) {
 259             waddch(boardwin, ACS_HLINE);
 260             waddch(boardwin, ACS_HLINE);
 261             waddch(boardwin, ACS_HLINE);
 262             waddch(boardwin, ACS_PLUS);
 263         }
 264         waddch(boardwin, ACS_HLINE);
 265         waddch(boardwin, ACS_HLINE);
 266         waddch(boardwin, ACS_HLINE);
 267         waddch(boardwin, ACS_RTEE);
 268     }
 269
 270     move(BOARDY + i * 2 - 1, BOARDX);
 271     waddch(boardwin, ACS_VLINE);
 272     for (j = 0; j < BWIDTH; j++) {
 273         waddch(boardwin, ' ');
 274         waddch(boardwin, ' ');
 275         waddch(boardwin, ' ');
 276         waddch(boardwin, ACS_VLINE);
 277     }
 278
 279     move(BOARDY + i * 2, BOARDX);
 280     waddch(boardwin, ACS_LLCORNER);
 281     for (j = 0; j < BWIDTH - 1; j++) {
 282         waddch(boardwin, ACS_HLINE);
 283         waddch(boardwin, ACS_HLINE);
 284         waddch(boardwin, ACS_HLINE);
 285         waddch(boardwin, ACS_BTEE);
 286     }
 287     waddch(boardwin, ACS_HLINE);
 288     waddch(boardwin, ACS_HLINE);
 289     waddch(boardwin, ACS_HLINE);
 290     waddch(boardwin, ACS_LRCORNER);
 291 }
 292
 293 static void
 294 mark_possibles(int prow, int pcol, chtype mark)
 295 {
 296     unsigned n;
 297
 298     for (n = 0; n < SIZEOF(offsets); n++) {
 299         if (chksqr(prow + offsets[n].y, pcol + offsets[n].x)) {
 300             cellmove(prow + offsets[n].y, pcol + offsets[n].x);
 301             waddch(boardwin, mark);
 302         }
 303     }
 304 }
 305
 306 static bool
 307 find_next_move(int *y, int *x)
 308 {
 309     unsigned j, k;
 310     int found = -1;
 311     int first = -1;
 312     int next = -1;
 313     int oldy, oldx;
 314     int newy, newx;
 315     bool result = FALSE;
 316
 317     if (movecount > 1) {
 318         oldy = history[movecount - 1].y;
 319         oldx = history[movecount - 1].x;
 320         for (j = 0; j < SIZEOF(offsets) * 2; j++) {
 321             k = j % SIZEOF(offsets);
 322             newy = oldy + offsets[k].y;
 323             newx = oldx + offsets[k].x;
 324             if (chksqr(newy, newx)) {
 325                 if (first < 0)
 326                     first = (int) k;
 327                 if (newy == *y
 328                     && newx == *x) {
 329                     found = (int) k;
 330                 } else if (found >= 0) {
 331                     next = (int) k;
 332                     break;
 333                 }
 334             }
 335         }
 336         if (found < 0)
 337             next = first;
 338         if (next >= 0) {
 339             *y = oldy + offsets[next].y;
 340             *x = oldx + offsets[next].x;
 341         }
 342         result = TRUE;
 343     }
 344     return result;
 345 }
 346
 347 static void
 348 count_next_moves(int y, int x)
 349 {
 350     int count = 0;
 351     unsigned j;
 352
 353     wprintw(msgwin, "\nMove %d", movecount);
 354     for (j = 0; j < SIZEOF(offsets); j++) {
 355         int newy = y + offsets[j].y;
 356         int newx = x + offsets[j].x;
 357         if (chksqr(newy, newx)) {
 358             ++count;
 359         }
 360     }
 361     wprintw(msgwin, ", gives %d choices", count);
 362     wclrtoeol(msgwin);
 363 }
 364
 365 static void
 366 unmarkcell(int row, int column)
 367 {
 368     cellmove(row, column);
 369     waddch(boardwin, '\b');
 370     waddch(boardwin, ' ');
 371     waddch(boardwin, minus);
 372     waddch(boardwin, ' ');
 373 }
 374
 375 static void
 376 markcell(chtype tchar, int row, int column)
 377 {
 378     cellmove(row, column);
 379     waddch(boardwin, '\b');
 380     waddch(boardwin, tchar);
 381     waddch(boardwin, tchar);
 382     waddch(boardwin, tchar);
 383 }
 384
 385 static void
 386 drawmove(chtype tchar, int oldy, int oldx, int row, int column)
 387 /* place the stars, update board & currents */
 388 {
 389     if (movecount <= 1) {
 390         int i, j;
 391
 392         for (i = 0; i < BDEPTH; i++) {
 393             for (j = 0; j < BWIDTH; j++) {
 394                 if (movecount == 0) {
 395                     unmarkcell(i, j);
 396                 } else {
 397                     cellmove(i, j);
 398                     if (winch(boardwin) == minus)
 399                         waddch(boardwin, movecount ? ' ' : minus);
 400                 }
 401             }
 402         }
 403     } else {
 404         markcell(tchar, oldy, oldx);
 405         mark_possibles(oldy, oldx, ' ');
 406     }
 407
 408     if (row >= 0 && column >= 0) {
 409         markcell(trail, row, column);
 410         mark_possibles(row, column, minus);
 411         board[row][column] = TRUE;
 412     }
 413
 414     wprintw(msgwin, "\nMove %d", movecount);
 415     if (trialcount != movecount)
 416         wprintw(msgwin, " (%d tries)", trialcount);
 417     wclrtoeol(msgwin);
 418 }
 419
 420 static int
 421 iabs(int num)
 422 {
 423     if (num < 0)
 424         return (-num);
 425     else
 426         return (num);
 427 }
 428
 429 static bool
 430 evalmove(int row, int column)
 431 /* evaluate move */
 432 {
 433     if (movecount == 1)
 434         return (TRUE);
 435     else if (board[row][column] == TRUE) {
 436         waddstr(msgwin, "\nYou've already been there.");
 437         return (FALSE);
 438     } else {
 439         int rdif = iabs(row - history[movecount - 1].y);
 440         int cdif = iabs(column - history[movecount - 1].x);
 441
 442         if (!((rdif == 1) && (cdif == 2)) && !((rdif == 2) && (cdif == 1))) {
 443             waddstr(msgwin, "\nThat's not a legal knight's move.");
 444             return (FALSE);
 445         }
 446     }
 447
 448     return (TRUE);
 449 }
 450
 451 static int
 452 completed(void)
 453 {
 454     int i, j, count = 0;
 455
 456     for (i = 0; i < BDEPTH; i++)
 457         for (j = 0; j < BWIDTH; j++)
 458             if (board[i][j] != 0)
 459                 count += 1;
 460     return (count == (BWIDTH * BDEPTH) ? -1 : count);
 461 }
 462
 463 static void
 464 no_previous_move(void)
 465 {
 466     waddstr(msgwin, "\nNo previous move.");
 467     beep();
 468 }
 469
 470 static void
 471 play(void)
 472 /* play the game */
 473 {
 474     bool keyhelp;               /* TRUE if keystroke help is up */
 475     int i, j, count;
 476     int lastcol = 0;            /* last location visited */
 477     int lastrow = 0;
 478     int ny = 0, nx = 0;
 479     int review = 0;             /* review history */
 480     int rw = 0, col = 0;        /* current row and column */
 481
 482     do {
 483         /* clear screen and draw board */
 484         werase(boardwin);
 485         werase(helpwin);
 486         werase(msgwin);
 487         dosquares();
 488         help1();
 489         wnoutrefresh(stdscr);
 490         wnoutrefresh(helpwin);
 491         wnoutrefresh(msgwin);
 492         wnoutrefresh(boardwin);
 493         doupdate();
 494
 495         movecount = 0;
 496         for (i = 0; i < BDEPTH; i++) {
 497             for (j = 0; j < BWIDTH; j++) {
 498                 board[i][j] = FALSE;
 499                 unmarkcell(i, j);
 500             }
 501         }
 502         memset(history, 0, sizeof(history));
 503         history[0].y = history[0].x = -1;
 504         history[1].y = history[1].x = -1;
 505         lastrow = lastcol = -2;
 506         movecount = 1;
 507         trialcount = 1;
 508         keyhelp = FALSE;
 509         show_help(&keyhelp);
 510
 511         for (;;) {
 512             if (rw != lastrow || col != lastcol) {
 513                 if (lastrow >= 0 && lastcol >= 0) {
 514                     cellmove(lastrow, lastcol);
 515                     if (board[lastrow][lastcol])
 516                         waddch(boardwin, trail);
 517                     else
 518                         waddch(boardwin, oldch);
 519                 }
 520
 521                 cellmove(rw, col);
 522                 oldch = winch(boardwin);
 523
 524                 lastrow = rw;
 525                 lastcol = col;
 526             }
 527             cellmove(rw, col);
 528             waddch(boardwin, plus);
 529             cellmove(rw, col);
 530
 531             wrefresh(msgwin);
 532
 533             switch (wgetch(boardwin)) {
 534             case 'k':
 535             case '8':
 536             case KEY_UP:
 537                 ny = rw + BDEPTH - 1;
 538                 nx = col;
 539                 break;
 540             case 'j':
 541             case '2':
 542             case KEY_DOWN:
 543                 ny = rw + 1;
 544                 nx = col;
 545                 break;
 546             case 'h':
 547             case '4':
 548             case KEY_LEFT:
 549                 ny = rw;
 550                 nx = col + BWIDTH - 1;
 551                 break;
 552             case 'l':
 553             case '6':
 554             case KEY_RIGHT:
 555                 ny = rw;
 556                 nx = col + 1;
 557                 break;
 558             case 'y':
 559             case '7':
 560             case KEY_A1:
 561                 ny = rw + BDEPTH - 1;
 562                 nx = col + BWIDTH - 1;
 563                 break;
 564             case 'b':
 565             case '1':
 566             case KEY_C1:
 567                 ny = rw + 1;
 568                 nx = col + BWIDTH - 1;
 569                 break;
 570             case 'u':
 571             case '9':
 572             case KEY_A3:
 573                 ny = rw + BDEPTH - 1;
 574                 nx = col + 1;
 575                 break;
 576             case 'n':
 577             case '3':
 578             case KEY_C3:
 579                 ny = rw + 1;
 580                 nx = col + 1;
 581                 break;
 582
 583 #ifdef KEY_MOUSE
 584             case KEY_MOUSE:
 585 #ifdef NCURSES_MOUSE_VERSION
 586                 {
 587                     MEVENT myevent;
 588
 589                     getmouse(&myevent);
 590                     if (myevent.y >= CY(0) && myevent.y <= CY(BDEPTH)
 591                         && myevent.x >= CX(0) && myevent.x <= CX(BWIDTH)) {
 592                         nx = CXINV(myevent.x);
 593                         ny = CYINV(myevent.y);
 594                         ungetch('\n');
 595                         break;
 596                     } else {
 597                         beep();
 598                         continue;
 599                     }
 600                 }
 601 #endif /* NCURSES_MOUSE_VERSION */
 602 #ifdef PDCURSES
 603                 {
 604                     int test_y, test_x;
 605                     request_mouse_pos();
 606                     test_y = MOUSE_Y_POS + 0;
 607                     test_x = MOUSE_X_POS + 1;
 608                     if (test_y >= CY(0) && test_y <= CY(BDEPTH)
 609                         && test_x >= CX(0) && test_x <= CX(BWIDTH)) {
 610                         ny = CYINV(test_y);
 611                         nx = CXINV(test_x);
 612                         wmove(helpwin, 0, 0);
 613                         wrefresh(helpwin);
 614                         ungetch('\n');
 615                     }
 616                     break;
 617                 }
 618 #endif /* PDCURSES */
 619 #endif /* KEY_MOUSE */
 620
 621             case KEY_B2:
 622             case '\n':
 623             case ' ':
 624                 review = 0;
 625                 if (evalmove(rw, col)) {
 626                     drawmove(trail,
 627                              history[movecount - 1].y,
 628                              history[movecount - 1].x,
 629                              rw, col);
 630                     history[movecount].y = (short) rw;
 631                     history[movecount].x = (short) col;
 632                     movecount++;
 633                     trialcount++;
 634
 635                     if (!chkmoves(rw, col)) {
 636                         if (completed() < 0) {
 637                             waddstr(msgwin, "\nYou won.");
 638                         } else {
 639                             waddstr(msgwin,
 640                                     "\nNo further moves are possible.");
 641                         }
 642                     }
 643                 } else {
 644                     beep();
 645                 }
 646                 break;
 647
 648             case KEY_UNDO:
 649             case KEY_BACKSPACE:
 650             case '\b':
 651                 review = 0;
 652                 if (movecount <= 0) {
 653                     no_previous_move();
 654                 } else if (movecount <= 1) {
 655                     ny = history[movecount].y;
 656                     nx = history[movecount].x;
 657                     if (nx < 0 || ny < 0) {
 658                         ny = (lastrow >= 0) ? lastrow : 0;
 659                         nx = (lastcol >= 0) ? lastcol : 0;
 660                     }
 661                     movecount = 0;
 662                     board[ny][nx] = FALSE;
 663                     oldch = minus;
 664                     drawmove(' ', ny, nx, -1, -1);
 665                     movecount = 1;
 666                     trialcount = 1;
 667                     no_previous_move();
 668                 } else {
 669                     int oldy = history[movecount - 1].y;
 670                     int oldx = history[movecount - 1].x;
 671
 672                     if (!board[rw][col]) {
 673                         cellmove(rw, col);
 674                         waddch(boardwin, ' ');
 675                     }
 676
 677                     board[oldy][oldx] = FALSE;
 678                     --movecount;
 679                     ny = history[movecount - 1].y;
 680                     nx = history[movecount - 1].x;
 681                     if (nx < 0 || ny < 0) {
 682                         ny = oldy;
 683                         nx = oldx;
 684                     }
 685                     drawmove(' ', oldy, oldx, ny, nx);
 686
 687                     /* avoid problems if we just changed the current cell */
 688                     cellmove(lastrow, lastcol);
 689                     oldch = winch(boardwin);
 690                 }
 691                 break;
 692
 693             case 'a':
 694                 nx = col;
 695                 ny = rw;
 696                 if (find_next_move(&ny, &nx))
 697                     count_next_moves(ny, nx);
 698                 else
 699                     beep();
 700                 break;
 701
 702             case 'F':
 703                 if (review > 0) {
 704                     review--;
 705                     ny = history[movecount - review - 1].y;
 706                     nx = history[movecount - review - 1].x;
 707                 } else {
 708                     beep();
 709                 }
 710                 break;
 711
 712             case 'B':
 713                 if (review < movecount - 2) {
 714                     review++;
 715                     ny = history[movecount - review - 1].y;
 716                     nx = history[movecount - review - 1].x;
 717                 } else {
 718                     beep();
 719                 }
 720                 break;
 721
 722             case KEY_REDO:
 723             case '\f':
 724             case 'r':
 725                 clearok(curscr, TRUE);
 726                 wnoutrefresh(stdscr);
 727                 wnoutrefresh(boardwin);
 728                 wnoutrefresh(msgwin);
 729                 wnoutrefresh(helpwin);
 730                 doupdate();
 731                 break;
 732
 733             case 'q':
 734             case 'x':
 735                 goto dropout;
 736
 737             case '?':
 738                 show_help(&keyhelp);
 739                 break;
 740
 741             default:
 742                 beep();
 743                 break;
 744             }
 745
 746             col = nx % BWIDTH;
 747             rw = ny % BDEPTH;
 748         }
 749
 750       dropout:
 751         if ((count = completed()) < 0)
 752             wprintw(msgwin, "\nYou won.  Care to try again? ");
 753         else
 754             wprintw(msgwin, "\n%d squares filled.  Try again? ", count);
 755         wclrtoeol(msgwin);
 756     } while
 757         (tolower(wgetch(msgwin)) == 'y');
 758 }
 759
 760 int
 761 main(int argc GCC_UNUSED, char *argv[]GCC_UNUSED)
 762 {
 763     init_program();
 764
 765     play();
 766
 767     endwin();
 768     ExitProgram(EXIT_SUCCESS);
 769 }
 770
 771 /* knight.c ends here */