#68
Sliding Tile Puzzle

  1. """Sliding Tile Puzzle, by Al Sweigart [email protected]
  2. Slide the numbered tiles into the correct order.
  3. This code is available at https://nostarch.com/big-book-small-python-programming
  4. Tags: large, game, puzzle"""
  5. 
  6. import random, sys
  7. 
  8. BLANK = '  '  # Note: This string is two spaces, not one.
  9. 
 10. 
 11. def main():
 12.     print('''Sliding Tile Puzzle, by Al Sweigart [email protected]
 13. 
 14.     Use the WASD keys to move the tiles
 15.     back into their original order:
 16.            1  2  3  4
 17.            5  6  7  8
 18.            9 10 11 12
 19.           13 14 15   ''')
 20.     input('Press Enter to begin...')
 21. 
 22.     gameBoard = getNewPuzzle()
 23. 
 24.     while True:
 25.         displayBoard(gameBoard)
 26.         playerMove = askForPlayerMove(gameBoard)
 27.         makeMove(gameBoard, playerMove)
 28. 
 29.         if gameBoard == getNewBoard():
 30.             print('You won!')
 31.             sys.exit()
 32. 
 33. 
 34. def getNewBoard():
 35.     """Return a list of lists that represents a new tile puzzle."""
 36.     return [['1 ', '5 ', '9 ', '13'], ['2 ', '6 ', '10', '14'],
 37.             ['3 ', '7 ', '11', '15'], ['4 ', '8 ', '12', BLANK]]
 38. 
 39. 
 40. def displayBoard(board):
 41.     """Display the given board on the screen."""
 42.     labels = [board[0][0], board[1][0], board[2][0], board[3][0],
 43.               board[0][1], board[1][1], board[2][1], board[3][1],
 44.               board[0][2], board[1][2], board[2][2], board[3][2],
 45.               board[0][3], board[1][3], board[2][3], board[3][3]]
 46.     boardToDraw = """
 47. +------+------+------+------+
 48. |      |      |      |      |
 49. |  {}  |  {}  |  {}  |  {}  |
 50. |      |      |      |      |
 51. +------+------+------+------+
 52. |      |      |      |      |
 53. |  {}  |  {}  |  {}  |  {}  |
 54. |      |      |      |      |
 55. +------+------+------+------+
 56. |      |      |      |      |
 57. |  {}  |  {}  |  {}  |  {}  |
 58. |      |      |      |      |
 59. +------+------+------+------+
 60. |      |      |      |      |
 61. |  {}  |  {}  |  {}  |  {}  |
 62. |      |      |      |      |
 63. +------+------+------+------+
 64. """.format(*labels)
 65.     print(boardToDraw)
 66. 
 67. 
 68. def findBlankSpace(board):
 69.     """Return an (x, y) tuple of the blank space's location."""
 70.     for x in range(4):
 71.         for y in range(4):
 72.             if board[x][y] == '  ':
 73.                 return (x, y)
 74. 
 75. 
 76. def askForPlayerMove(board):
 77.     """Let the player select a tile to slide."""
 78.     blankx, blanky = findBlankSpace(board)
 79. 
 80.     w = 'W' if blanky != 3 else ' '
 81.     a = 'A' if blankx != 3 else ' '
 82.     s = 'S' if blanky != 0 else ' '
 83.     d = 'D' if blankx != 0 else ' '
 84. 
 85.     while True:
 86.         print('                          ({})'.format(w))
 87.         print('Enter WASD (or QUIT): ({}) ({}) ({})'.format(a, s, d))
 88. 
 89.         response = input('> ').upper()
 90.         if response == 'QUIT':
 91.             sys.exit()
 92.         if response in (w + a + s + d).replace(' ', ''):
 93.             return response
 94. 
 95. 
 96. def makeMove(board, move):
 97.     """Carry out the given move on the given board."""
 98.     # Note: This function assumes that the move is valid.
 99.     bx, by = findBlankSpace(board)
100. 
101.     if move == 'W':
102.         board[bx][by], board[bx][by+1] = board[bx][by+1], board[bx][by]
103.     elif move == 'A':
104.         board[bx][by], board[bx+1][by] = board[bx+1][by], board[bx][by]
105.     elif move == 'S':
106.         board[bx][by], board[bx][by-1] = board[bx][by-1], board[bx][by]
107.     elif move == 'D':
108.         board[bx][by], board[bx-1][by] = board[bx-1][by], board[bx][by]
109. 
110. 
111. def makeRandomMove(board):
112.     """Perform a slide in a random direction."""
113.     blankx, blanky = findBlankSpace(board)
114.     validMoves = []
115.     if blanky != 3:
116.         validMoves.append('W')
117.     if blankx != 3:
118.         validMoves.append('A')
119.     if blanky != 0:
120.         validMoves.append('S')
121.     if blankx != 0:
122.         validMoves.append('D')
123. 
124.     makeMove(board, random.choice(validMoves))
125. 
126. 
127. def getNewPuzzle(moves=200):
128.     """Get a new puzzle by making random slides from a solved state."""
129.     board = getNewBoard()
130. 
131.     for i in range(moves):
132.         makeRandomMove(board)
133.     return board
134. 
135. 
136. # If this program was run (instead of imported), run the game:
137. if __name__ == '__main__':
138.     main()