def solve(self) -> bool:
"""Solve the sudoku board recursively using a backtracking algorithm
and shows the steps visually."""
coordinates = solver.find_empty(self.puzzle)
if not coordinates:
return True
row, col = coordinates
grid_x = col // 3
grid_y = row // 3
square_size = (55, 55)
for i in range(1, 10):
self.clock.tick(self.speed)
self.display.fill(DARK_BLUE)
self.draw_empty_board()
self.draw_numbers(DARK_BLUE)
self.draw_buttons()
for event in pygame.event.get():
if event.type == pygame.QUIT:
pygame.quit()
sys.exit()
if event.type == pygame.MOUSEBUTTONDOWN:
mouse_pos = pygame.mouse.get_pos()
if 688 < mouse_pos[0] < 1019 and 550 < mouse_pos[1] < 605:
self.new_speed()
if 730 < mouse_pos[0] < 970 and 340 < mouse_pos[1] < 410:
self.quick_solve(use_copy=True)
return True
if solver.is_valid(self.puzzle, row, col, i):
self.puzzle[row][col] = i
self.draw_empty_board()
pygame.draw.rect(self.display, self.GREEN,
((45 + (col * 60) + (grid_x * 5), 120 +
(row * 60) + (grid_y * 5)), square_size))
self.draw_numbers(self.GREEN)
self.draw_numbers(self.DARK_BLUE, use_copy=True)
pygame.display.update()
if self.solve():
return True
self.puzzle[row][col] = 0
self.draw_empty_board()
pygame.draw.rect(self.display, self.RED,
((45 + (col * 60) + (grid_x * 5), 120 +
(row * 60) + (grid_y * 5)), square_size))
self.draw_numbers(self.GREEN)
self.draw_numbers(self.DARK_BLUE, use_copy=True)
pygame.display.update()
return False
def place(self, val):
row, col = self.selected
self.cells[row][col].set_val(val)
# Check if placement is valid to keep track for completion
if solver.is_valid(self.state, col, row, val):
self.cells[row][col].valid = True
else:
self.cells[row][col].valid = False
self.update_state()
def update_board(self, position, number):
if number == -1 or position == None:
return False
row, column = map(lambda x: (x - self.PADDING) // self.CELL_SIZE, position)
if row < 0 or row > 8 or column < 0 or column > 8:
return False
if self.INITIAL_BOARD[row][column] == 0:
if is_valid(self.board, (row, column), number) or number == 0:
self.board[row][column] = number
self.invalid_cell = None
else:
self.invalid_cell = position
def place(self, val):
row, col = self.selected
if self.cubes[row][col].value == 0:
self.cubes[row][col].set(val)
self.update_model()
if is_valid(self.model, val,
(row, col)) and solve_board(self.model):
return True
else:
self.cubes[row][col].set(0)
self.cubes[row][col].set_temp(0)
self.update_model()
return False
def main():
for team_id, task_id in enumerate(task_ids):
print("Generating task for team" , team_id)
flag = flags[team_id]
task_folder = os.path.join(PACKAGE_PATH, task_id)
os.makedirs(task_folder, exist_ok=True)
task_file = os.path.join(task_folder, "scanner")
os.system("python3 {} {} {}".format(GENERATOR, flag, task_file))
assert is_valid(task_file, flag)
def place_num(self, value):
"""Check validation of a number to place in the board"""
row, col = self.selected
if self.cubes[row][col].value == 0:
self.cubes[row][col].set_value(value)
self.update_model()
if is_valid(self.model, value, (row, col)) and solve(self.model):
return True
elif is_valid_sudoku(self.model):
return True
else:
self.cubes[row][col].set_value(0)
self.cubes[row][col].set_temporary(0)
self.update_model()
return False
def solve_gui(board):
"""
Solves the given sudoku board using backtracking algorithm.
Added graphic capabilities on top of solver.solve method.
"""
# Find empty space. If none exists, return true.
empty = solver.find_zero(board)
if not empty:
return True
row, col = empty
# Try all possible values in the coordinate of empty space.
# If value is valid, recurse the 'solve' method.
# Otherwise, reset value to 0 and try another value to recurse.
for i in range(1, 10):
if solver.is_valid(row, col, i, board):
board[row][col] = i
delay_draw(col, row, i, black, 90)
if solve_gui(board):
return True
board[row][col] = 0
delay_draw(col, row, i, blue, 90)
return False
def test_valid(self):
self.assertTrue(is_valid(self.valid))
def test_same_diag(self):
self.assertFalse(is_valid(self.invalid_diag))
def test_same_col(self):
self.assertFalse(is_valid(self.invalid_row))
def __init__(self,
img_path=None,
img=None,
max_size=1000,
predict_threshold=0.5,
overlay=True):
"""
Initializes the Sudoku grid from an image.
Args:
img_path (str): path to the image of sudoku
img (numpy.ndarray): loaded image instead of img_path
max_size (int): maximum allowed size of image
predict_threshold (float): minimun threshold to predict digit
overlay (bool): generate the output image
"""
if img_path is None and img is None:
raise ValueError("img_path and img both cannot be None.")
if img_path is not None and img is not None:
raise ValueError("Only one of img_path and img can be used.")
if img_path:
if not os.path.exists(img_path):
raise FileNotFoundError(img_path)
img = cv2.imread(img_path, cv2.IMREAD_COLOR)
self.status = 'processing'
self.original = ip_utils.scale_down(img, max_size)
self.solved_image = None
self.grayscale = cv2.cvtColor(self.original.copy(), cv2.COLOR_BGR2GRAY)
# crop and warp to get the sudoku grid
self.cropped, self.crop_matrix, self.crop_corners = ip_utils.crop_grid(
self.grayscale)
self.cropped_color = None
# divide the grid into cells
self.grid_cells = ip_utils.divide_into_cells(self.cropped)
# extract the digits from the cells
self.digits = ip_utils.get_digits(self.cropped,
self.grid_cells,
size=28)
# convert the images of digits to digits using digit recognition model
self.board = [[0] * 9 for _ in range(9)]
self.solved_board = None
pred_indices = []
pred_digits = []
for i, digit in enumerate(self.digits):
# if digit is present in cell
if cv2.countNonZero(digit) > 0:
pred_digits.append(digit)
pred_indices.append((i // 9, i % 9))
predicted = predict_digits(np.array(pred_digits),
threshold=predict_threshold)
for (i, j), d in zip(pred_indices, predicted):
self.board[i][j] = d
# check if recognized sudoku puzzle is valid
if not solver.is_valid(self.board):
self.status = 'Unable to detect a valid Sudoku puzzle.'
return
self.solved_board = copy.deepcopy(self.board)
if solver.solve(self.solved_board, validate=False):
if overlay:
self.solved_image = self.digits_overlay()
self.status = 'solved'
else:
self.status = 'Either the sudoku is invalid or image is blurry.'
def run(board):
init_board()
set_board(board)
orig_board = copy.deepcopy(board)
selected = False
valued = False
prev_val = -1
while True:
for event in pygame.event.get():
# Game exit.
if event.type == pygame.QUIT:
pygame.quit()
exit()
# Key pressed.
elif event.type == pygame.KEYDOWN:
# Pressed space bar which solves the sudoku game using backtracking.
if event.key == pygame.K_SPACE:
if selected:
reset_selected_box(valued, prev_pos, prev_val)
selected = False
valued = False
solve_gui(board)
# Pressed number character with box selected.
elif event.key in [
pygame.K_1, pygame.K_2, pygame.K_3, pygame.K_4,
pygame.K_5, pygame.K_6, pygame.K_7, pygame.K_8,
pygame.K_9
]:
if selected:
reset_selected_box(valued, prev_pos, prev_val)
valued = True
delay_draw(prev_pos[0] // 55, prev_pos[1] // 55,
event.unicode, grey, 0)
prev_val = event.unicode
# Pressing enter with a box filled in with value.
# Value is either valid or invalid.
elif event.key == pygame.K_RETURN:
# Enter only works if there is a box selected and valued.
if selected & valued:
value = int(prev_val)
col, row = prev_pos[0] // 55, prev_pos[1] // 55
# Input is valid.
if solver.is_valid(row, col, value, board):
board[row][col] = value
delay_draw(col, row, value, green, 200)
delay_draw(col, row, value, black, 0)
# Input is invalid.
else:
delay_draw(col, row, value, red, 200)
delay_draw(col, row, value, blue, 0)
selected = False
valued = False
prev_val = -1
# Mouse selection.
elif event.type == pygame.MOUSEBUTTONDOWN:
x, y = pygame.mouse.get_pos()
col, row = x // 55, y // 55
# Selected box can be changed.
if empty_pos(x, y, orig_board):
if board[row][col] != 0:
delay_draw(col, row, board[row][col], blue, 0)
board[row][col] = 0
if selected:
reset_selected_box(valued, prev_pos, prev_val)
valued = False
delay_draw(col, row, "?", grey, 0)
selected = True
prev_pos = (x, y)