Опубликован: 12.07.2013 | Доступ: свободный | Студентов: 978 / 36 | Длительность: 37:41:00
Лекция 13:

Sonar Treasure Hunt

< Лекция 12 || Лекция 13: 12345 || Лекция 14 >

Sonar's Source Code

Knowing about Cartesian coordinates, number lines, negative numbers, and absolute values will help us out with our Sonar game. If you do not think you understand these concepts, go back to "Bagels" to brush up. Below is the source code for the game. Type it into a new file, then save the file as sonar.py and run it by pressing the F5 key. You do not need to understand the code to type it in or play the game, the source code will be explained later.

Also, you can download the source code from the book's website at the URL http://inventwithpython.com/chapter13.

sonar.py

This code can be downloaded from http://inventwithpyt.hon.com/sonar.py

If you get errors after typing this code in, compare it to the book's code with the online

diff tool at http://inventwithpython.com/diff or email the author at

al@inventwithpython.com

1. # Sonar 
2.
3.  import random
4.  import sys 
5.
6. def drawBoard(board):
7.     # Draw the board data structure. 
8.
9.     hline = '    ' # initial space for the numbers down the left side of the board
10.      for i in range(1, 6) :
11.         hline += (' ' * 9) + str(i)
12.
13.     # print the numbers across the top
14.     print(hline)
15.     print('   ' + ('0123456789' * 6))
16.     print()
17.
18.     # print each of the 15 rows
19.      for i in range(15):
20.         # single-digit numbers need to be padded with an extra space
21.          if i < 10:
22.             extraSpace = ' '
23.        else:
24.                             extraSpace = ' '
25.                    print('%s%s %s %s' % (extraSpace, i, getRow
(board, i), i)) 
26.
27.     # print the numbers across the bottom
28.     print()
29.     print('   ' + ('0123456789' * 6))
30.     print(hline) 
31.
32.
33. def getRow(board, row):
34.     # Return a string from the board data structure at a certain row.
35.     boardRow = ''
36.     for i in range(60):
37.         boardRow += board[i][row]
38.     return boardRow 
39.
40. def getNewBoard():
41.     # Create a new 60x15 board data structure.
42.     board = []
43.     for x in range(60): # the main list is a list of 60 lists
44.         board.append([])
45.         for y in range(15): # each list in the main list has 15 single-character strings
46.             # use different characters for the ocean to make it more readable.
47.             if random.randint(0, 1) == 0:
48.                 board[x].append('~')
49.             else:
50.                 board[x].append('`')
51.     return board 52.
53. def getRandomChests(numChests):
54.     # Create a list of chest data structures (two-item lists of x, y int coordinates)
55.     chests = []
56.     for i in range(numChests):
57.         chests.append([random.randint(0, 59), random.randint(0, 14)])
58.     return chests 59.
60. def isValidMove(x, y):
61.     # Return True if the coordinates are on the board, otherwise False.
62.     return x >= 0 and x <= 59 and y >= 0 and y <= 14 63.
64. def makeMove(board, chests, x, y):
65.     # Change the board data structure with a sonar device character. Remove treasure chests
66.     # from the chests list as they are found. Return False if this is an invalid move.
67.     # Otherwise, return the string of the result of this move.
68.     if not isValidMove(x, y):
69.         return False 
70.
71.     smallestDistance = 100 # any chest will be closer than 100.
72.     for cx, cy in chests:
73.         if abs(cx - x) > abs(cy - y):
74.             distance = abs(cx - x)
75.         else:
76.             distance = abs(cy - y) 
77.
78.         if distance < smallestDistance: # we want the closest treasure chest.
79.             smallestDistance = distance 
80.
81.     if smallestDistance == 0:
82.         # xy is directly on a treasure chest!
83.         chests.remove([x, y])
84.         return 'You have found a sunken treasure chest!'
85.     else:
86.         if smallestDistance < 10:
87.             board[x][y] = str(smallestDistance)
88.             return 'Treasure detected at a distance of %s from the sonar device.' % (smallestDistance)
89.         else:
90.             board[x][y] = 'O'
91.             return 'Sonar did not detect anything. All treasure chests out of range.'
92. 
93.
94. def enterPlayerMove():
95.     # Let the player type in her move. Return a two-item list of int xy coordinates.
96.     print('Where do you want to drop the next sonar device? (0-59 0-14) (or type quit)')
97.     while True:
98.         move = input()
99.         if move.lower() == 'quit':
100.             print('Thanks for playing!')
101.             sys.exit() 102.
103.         move = move.split()
104.         if len(move) == 2 and move[0].isdigit() and move [1].isdigit() and isValidMove(int(move[0]), int(move[1])):
105.             return [int(move[0]), int(move[1])]
106.         print('Enter a number from 0 to 59, a space, then a number from 0 to 14.')
107. 
108.
109. def playAgain():
110.     # This function returns True if the player wants to play again, otherwise it returns False.
111.     print('Do you want to play again? (yes or no)')
112.     return input().lower().startswith('y') 
113.
114.
115. def showInstructions():
116.     print('''Instructions:
117. You are the captain of the Simon, a treasure-hunting ship. Your current mission
118. is to find the three sunken treasure chests that are lurking in the part of the
119. ocean you are in and collect them. 
120.
121. To play, enter the coordinates of the point in the ocean you wish to drop a
122. sonar device. The sonar can find out how far away the closest chest is to it.
123. For example, the d below marks where the device was dropped, and the 2's
124. represent distances of 2 away from the device. The 4's represent
125. distances of 4 away from the device. 126.
127.     444444444
128.     4       4
129.     4 22222 4
130.     4 2   2 4
131.     4 2 d 2 4
132.     4 2   2 4
133.     4 22222 4
134.     4       4
135.     444444444
136. Press enter to continue...''')
137.     input() 
138.
139.     print('''For example, here is a treasure chest (the c) located a distance of 2 away
140. from the sonar device (the d): 
141.
142.     22222
143.     c   2
144.     2 d 2
145.     2   2
146.     22222 
147.
148. The point where the device was dropped will be marked with
a 2. 
149.
150. The treasure chests don't move around. Sonar devices can detect treasure
151. chests up to a distance of 9. If all chests are out of range, the point
152. will be marked with O 153.
154. If a device is directly dropped on a treasure chest, you have discovered
155. the location of the chest, and it will be collected. The sonar device will
156. remain there. 
157.
158. When you collect a chest, all sonar devices will update to locate the next
159. closest sunken treasure chest.
160. Press enter to continue...''')
161.     input()
162.     print() 
163.
164.
165. print('S O N A R !')
166. print()
167. print('Would you like to view the instructions? (yes/no)')
168. if input().lower().startswith('y'):
169.     showInstructions() 
170.
171. while True:
172.     # game setup
173.     sonarDevices = 16
174.     theBoard = getNewBoard()
175.     theChests = getRandomChests(3)
176.     drawBoard(theBoard)
177.     previousMoves = [] 178.
179.     while sonarDevices > 0:
180.         # Start of a turn: 181.
182.         # show sonar device/chest status
183.         if sonarDevices > 1: extraSsonar = 's'
184.         else: extraSsonar = ''
185.         if len(theChests) > 1: extraSchest = 's'
186.         else: extraSchest = ''
187.         print('You have %s sonar device%s left. %s treasure chest%s remaining.' %
  (sonarDevices, extraSsonar, len(theChests), extraSchest))
188.
189.         x, y = enterPlayerMove()
190.         previousMoves.append([x, y]) # we must track all moves so that sonar devices can be updated.
191.
192.         moveResult = makeMove(theBoard, theChests, x, y)
193.         if moveResult == False:
194.             continue
195.         else:
196.             if moveResult == 'You have found a sunken treasure chest!':
197.                 # update all the sonar devices currently on the map.
198.                 for x, y in previousMoves:
199.                     makeMove(theBoard, theChests, x, y)
200.             drawBoard(theBoard)
201.             print(moveResult) 
202.
203.         if len(theChests) == 0:
204.             print('You have found all the sunken treasure chests! Congratulations and good game!')
205.                             break
206.
207.                     sonarDevices -= 1
208.
209.      if sonarDevices == 0:
210.         print('We\'ve run out of sonar devices! Now we have to turn the ship around and head')
211.         print('for home with treasure chests still out there! Game over.')
212.         print('    The remaining chests were here:')
213.          for x, y in theChests:
214.             print('    %s, %s' % (x, y)) 215 .
216.      if not playAgain() :
217.          sys.exit()
< Лекция 12 || Лекция 13: 12345 || Лекция 14 >