I am Currently working on a minesweeper algorithm for a cs50 assignment. There seems to be an issue with my code. (Inside the minesweeper class)
The program needs both minesweeper.py and runner.py and is executed with "python runner.py"
Upon running it with python runner.py it gives me a RuntimeError:
Traceback (most recent call last):
File "C:\Users\seng\Downloads\minesweeper\minesweeper\runner.py", line 220, in <module>
ai.add_knowledge(move, nearby)
File "C:\Users\seng\Downloads\minesweeper\minesweeper\minesweeper.py", line 230, in add_knowledge
self.updateknowledge()
File "C:\Users\seng\Downloads\minesweeper\minesweeper\minesweeper.py", line 274, in updateknowledge
for safe in safes:
RuntimeError: Set changed size during iteration
minesweeper.py
import itertools
import random
import copy
class Minesweeper():
"""
Minesweeper game representation
"""
def __init__(self, height=8, width=8, mines=8):
# Set initial width, height, and number of mines
self.height = height
self.width = width
self.mines = set()
# Initialize an empty field with no mines
self.board = []
for i in range(self.height):
row = []
for j in range(self.width):
row.append(False)
self.board.append(row)
# Add mines randomly
while len(self.mines) != mines:
i = random.randrange(height)
j = random.randrange(width)
if not self.board[i][j]:
self.mines.add((i, j))
self.board[i][j] = True
# At first, player has found no mines
self.mines_found = set()
def print(self):
"""
Prints a text-based representation
of where mines are located.
"""
for i in range(self.height):
print("--" * self.width + "-")
for j in range(self.width):
if self.board[i][j]:
print("|X", end="")
else:
print("| ", end="")
print("|")
print("--" * self.width + "-")
def is_mine(self, cell):
i, j = cell
return self.board[i][j]
def nearby_mines(self, cell):
"""
Returns the number of mines that are
within one row and column of a given cell,
not including the cell itself.
"""
# Keep count of nearby mines
count = 0
# Loop over all cells within one row and column
for i in range(cell[0] - 1, cell[0] + 2):
for j in range(cell[1] - 1, cell[1] + 2):
# Ignore the cell itself
if (i, j) == cell:
continue
# Update count if cell in bounds and is mine
if 0 <= i < self.height and 0 <= j < self.width:
if self.board[i][j]:
count += 1
return count
def won(self):
"""
Checks if all mines have been flagged.
"""
return self.mines_found == self.mines
class Sentence():
"""
Logical statement about a Minesweeper game
A sentence consists of a set of board cells,
and a count of the number of those cells which are mines.
"""
def __init__(self, cells, count):
self.cells = set(cells)
self.count = count
def __eq__(self, other):
return self.cells == other.cells and self.count == other.count
def __str__(self):
return f"{self.cells} = {self.count}"
def known_mines(self):
"""
Returns the set of all cells in self.cells known to be mines.
"""
if len(self.cells) == self.count:
return self.cells
def known_safes(self):
"""
Returns the set of all cells in self.cells known to be safe.
"""
if 0 == self.count:
return self.cells
def mark_mine(self, cell):
"""
Updates internal knowledge representation given the fact that
a cell is known to be a mine.
"""
if cell in self.cells:
self.cells.remove(cell)
self.count -= 1
def mark_safe(self, cell):
"""
Updates internal knowledge representation given the fact that
a cell is known to be safe.
"""
if cell in self.cells:
self.cells.remove(cell)
class MinesweeperAI():
"""
Minesweeper game player
"""
def __init__(self, height=8, width=8):
# Set initial height and width
self.height = height
self.width = width
# Keep track of which cells have been clicked on
self.moves_made = set()
# Keep track of cells known to be safe or mines
self.mines = set()
self.safes = set()
# List of sentences about the game known to be true
self.knowledge = []
def mark_mine(self, cell):
"""
Marks a cell as a mine, and updates all knowledge
to mark that cell as a mine as well.
"""
self.mines.add(cell)
for sentence in self.knowledge:
sentence.mark_mine(cell)
def mark_safe(self, cell):
"""
Marks a cell as safe, and updates all knowledge
to mark that cell as safe as well.
"""
self.safes.add(cell)
for sentence in self.knowledge:
sentence.mark_safe(cell)
def add_knowledge(self, cell, count):
"""
Called when the Minesweeper board tells us, for a given
safe cell, how many neighboring cells have mines in them.
This function should:
1) mark the cell as a move that has been made
2) mark the cell as safe
3) add a new sentence to the AI's knowledge base
based on the value of `cell` and `count`
4) mark any additional cells as safe or as mines
if it can be concluded based on the AI's knowledge base
5) add any new sentences to the AI's knowledge base
if they can be inferred from existing knowledge
"""
#1
self.moves_made.add(cell)
#2
self.mark_safe(cell)
#3
i, j = cell
removecell = []
addcell = [(i-1, j-1), (i-1, j), (i-1, j+1),
(i, j-1), (i, j+1),
(i+1, j-1), (i+1, j), (i+1, j + 1),]
for c in addcell:
if c[0] < 0 or c[0] > 7 or c[1] < 0 or c[1] > 7:
removecell.append(c)
for c in removecell:
addcell.remove(c)
removecell = []
for c in addcell:
if c in self.mines:
removecell.append(c)
count -= len(removecell)
for c in removecell:
addcell.remove(c)
removecell = []
for c in addcell:
if c in self.safes:
removecell.append(c)
for c in removecell:
addcell.remove(c)
#need filter for empty
newsentence = Sentence(addcell, count)
if len(newsentence.cells) > 0:
self.knowledge.append(newsentence)
print("dfs")
self.updateknowledge()
print("2")
self.inference()
print("3")
def inference(self):
for sentence1 in self.knowledge:
for sentence2 in self.knowledge:
if sentence1.cells.issubset(sentence2.cells):
new_cells = sentence2.cells - sentence1.cells
new_count = sentence2.count - sentence1.count
new_sentence = Sentence(new_cells, new_count)
if new_sentence not in self.knowledge:
self.knowledge.append(new_sentence)
self.updateknowledge()
def updateknowledge(self):
keepgoing = True
while keepgoing:
keepgoing = False
for sentence in self.knowledge:
mines = sentence.known_mines()
if mines:
keepgoing = True
for mine in mines:
self.mark_mine(mine)
safes = sentence.known_safes()
if safes:
keepgoing = True
for safe in safes:
self.mark_safe(safe)
def make_safe_move(self):
"""
Returns a safe cell to choose on the Minesweeper board.
The move must be known to be safe, and not already a move
that has been made.
This function may use the knowledge in self.mines, self.safes
and self.moves_made, but should not modify any of those values.
"""
for safe in self.safes:
if safe not in self.moves_made:
return safe
return None
def make_random_move(self):
"""
Returns a move to make on the Minesweeper board.
Should choose randomly among cells that:
1) have not already been chosen, and
2) are not known to be mines
"""
moves = len(self.moves_made) + len(self.mines)
if moves == 64:
return None
while True:
i = random.randrange(self.height)
j = random.randrange(self.height)
if (i, j) not in self.moves_made and (i, j) not in self.mines:
return (i, j)
runner.py
import pygame
import sys
import time
from minesweeper import Minesweeper, MinesweeperAI
HEIGHT = 8
WIDTH = 8
MINES = 8
# Colors
BLACK = (0, 0, 0)
GRAY = (180, 180, 180)
WHITE = (255, 255, 255)
# Create game
pygame.init()
size = width, height = 600, 400
screen = pygame.display.set_mode(size)
# Fonts
OPEN_SANS = "assets/fonts/OpenSans-Regular.ttf"
smallFont = pygame.font.Font(OPEN_SANS, 20)
mediumFont = pygame.font.Font(OPEN_SANS, 28)
largeFont = pygame.font.Font(OPEN_SANS, 40)
# Compute board size
BOARD_PADDING = 20
board_width = ((2 / 3) * width) - (BOARD_PADDING * 2)
board_height = height - (BOARD_PADDING * 2)
cell_size = int(min(board_width / WIDTH, board_height / HEIGHT))
board_origin = (BOARD_PADDING, BOARD_PADDING)
# Add images
flag = pygame.image.load("assets/images/flag.png")
flag = pygame.transform.scale(flag, (cell_size, cell_size))
mine = pygame.image.load("assets/images/mine.png")
mine = pygame.transform.scale(mine, (cell_size, cell_size))
# Create game and AI agent
game = Minesweeper(height=HEIGHT, width=WIDTH, mines=MINES)
ai = MinesweeperAI(height=HEIGHT, width=WIDTH)
# Keep track of revealed cells, flagged cells, and if a mine was hit
revealed = set()
flags = set()
lost = False
# Show instructions initially
instructions = True
while True:
# Check if game quit
for event in pygame.event.get():
if event.type == pygame.QUIT:
sys.exit()
screen.fill(BLACK)
# Show game instructions
if instructions:
# Title
title = largeFont.render("Play Minesweeper", True, WHITE)
titleRect = title.get_rect()
titleRect.center = ((width / 2), 50)
screen.blit(title, titleRect)
# Rules
rules = [
"Click a cell to reveal it.",
"Right-click a cell to mark it as a mine.",
"Mark all mines successfully to win!"
]
for i, rule in enumerate(rules):
line = smallFont.render(rule, True, WHITE)
lineRect = line.get_rect()
lineRect.center = ((width / 2), 150 + 30 * i)
screen.blit(line, lineRect)
# Play game button
buttonRect = pygame.Rect((width / 4), (3 / 4) * height, width / 2, 50)
buttonText = mediumFont.render("Play Game", True, BLACK)
buttonTextRect = buttonText.get_rect()
buttonTextRect.center = buttonRect.center
pygame.draw.rect(screen, WHITE, buttonRect)
screen.blit(buttonText, buttonTextRect)
# Check if play button clicked
click, _, _ = pygame.mouse.get_pressed()
if click == 1:
mouse = pygame.mouse.get_pos()
if buttonRect.collidepoint(mouse):
instructions = False
time.sleep(0.3)
pygame.display.flip()
continue
# Draw board
cells = []
for i in range(HEIGHT):
row = []
for j in range(WIDTH):
# Draw rectangle for cell
rect = pygame.Rect(
board_origin[0] + j * cell_size,
board_origin[1] + i * cell_size,
cell_size, cell_size
)
pygame.draw.rect(screen, GRAY, rect)
pygame.draw.rect(screen, WHITE, rect, 3)
# Add a mine, flag, or number if needed
if game.is_mine((i, j)) and lost:
screen.blit(mine, rect)
elif (i, j) in flags:
screen.blit(flag, rect)
elif (i, j) in revealed:
neighbors = smallFont.render(
str(game.nearby_mines((i, j))),
True, BLACK
)
neighborsTextRect = neighbors.get_rect()
neighborsTextRect.center = rect.center
screen.blit(neighbors, neighborsTextRect)
row.append(rect)
cells.append(row)
# AI Move button
aiButton = pygame.Rect(
(2 / 3) * width + BOARD_PADDING, (1 / 3) * height - 50,
(width / 3) - BOARD_PADDING * 2, 50
)
buttonText = mediumFont.render("AI Move", True, BLACK)
buttonRect = buttonText.get_rect()
buttonRect.center = aiButton.center
pygame.draw.rect(screen, WHITE, aiButton)
screen.blit(buttonText, buttonRect)
# Reset button
resetButton = pygame.Rect(
(2 / 3) * width + BOARD_PADDING, (1 / 3) * height + 20,
(width / 3) - BOARD_PADDING * 2, 50
)
buttonText = mediumFont.render("Reset", True, BLACK)
buttonRect = buttonText.get_rect()
buttonRect.center = resetButton.center
pygame.draw.rect(screen, WHITE, resetButton)
screen.blit(buttonText, buttonRect)
# Display text
text = "Lost" if lost else "Won" if game.mines == flags else ""
text = mediumFont.render(text, True, WHITE)
textRect = text.get_rect()
textRect.center = ((5 / 6) * width, (2 / 3) * height)
screen.blit(text, textRect)
move = None
left, _, right = pygame.mouse.get_pressed()
# Check for a right-click to toggle flagging
if right == 1 and not lost:
mouse = pygame.mouse.get_pos()
for i in range(HEIGHT):
for j in range(WIDTH):
if cells[i][j].collidepoint(mouse) and (i, j) not in revealed:
if (i, j) in flags:
flags.remove((i, j))
else:
flags.add((i, j))
time.sleep(0.2)
elif left == 1:
mouse = pygame.mouse.get_pos()
# If AI button clicked, make an AI move
if aiButton.collidepoint(mouse) and not lost:
move = ai.make_safe_move()
if move is None:
move = ai.make_random_move()
if move is None:
flags = ai.mines.copy()
print("No moves left to make.")
else:
print("No known safe moves, AI making random move.")
else:
print("AI making safe move.")
time.sleep(0.2)
# Reset game state
elif resetButton.collidepoint(mouse):
game = Minesweeper(height=HEIGHT, width=WIDTH, mines=MINES)
ai = MinesweeperAI(height=HEIGHT, width=WIDTH)
revealed = set()
flags = set()
lost = False
continue
# User-made move
elif not lost:
for i in range(HEIGHT):
for j in range(WIDTH):
if (cells[i][j].collidepoint(mouse)
and (i, j) not in flags
and (i, j) not in revealed):
move = (i, j)
# Make move and update AI knowledge
if move:
if game.is_mine(move):
lost = True
else:
nearby = game.nearby_mines(move)
revealed.add(move)
ai.add_knowledge(move, nearby)
pygame.display.flip()
During the iteration over safes (the cells of a Sentence) you call self.mark_safe(safe). That removes the cell in cells on which you iter. But you cannot change a set during iteration.
Grab a shallow copy of safes and iterate over it instead.
class MinesweeperAI:
def updateknowledge(self):
...
safes = sentence.known_safes()
if safes:
keepgoing = True
for safe in safes.copy():
self.mark_safe(safe)