Jake Pullen
66 lines
1.8 KiB
Python
66 lines
1.8 KiB
Python
testing = 0
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if not testing:
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with open(r'2024/04\input.txt', 'r') as file:
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input = file.read()
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else:
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input = '''.M.S......
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..A..MSMS.
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.M.S.MAA..
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..A.ASMSM.
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.M.S.M....
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..........
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S.S.S.S.S.
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.A.A.A.A..
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M.M.M.M.M.
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..........'''
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# word search,
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# allows words to be horizontal, vertical, diagonal, written backwards, or even overlapping other words
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# test input has 18 words
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# part 2 calls for looking for 2x 'MAS' in the shape of an 'X'
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# we can now ignore the NESW directions
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# we should just check the diagonals of any 'A' we find
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# if it has 2 'MAS' in the diagonals, we have a match
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# turn the input into a list of lists so we can grid reference it
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lines = input.split('\n')
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grid = [list(line) for line in lines]
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directions = {
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'north_east': (1, -1),
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'south_west': (-1, 1),
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'south_east': (1, 1),
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'north_west': (-1, -1),
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}
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grid_x_len = len(grid[0])
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grid_y_len = len(grid)
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# print(grid)
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xmas_count = 0
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# search for 'A's
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for y, row in enumerate(grid):
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for x, cell in enumerate(row):
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if cell != 'A':
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continue
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# we found an 'A', check diagonals for 'M' and 'S'
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if not (0 <= x + 1 < grid_x_len and 0 <= y + 1 < grid_y_len and
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0 <= x - 1 < grid_x_len and 0 <= y - 1 < grid_y_len):
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# we are at the edge of the grid, no need to check
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continue
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# take the character from the diagonal, including the middle 'A'
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word_to_check = grid[y + 1][x + 1] + grid[y][x] + grid[y - 1][x - 1]
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if word_to_check == 'MAS' or word_to_check == 'SAM':
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# one diagonal has 'MAS', check the other
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word_to_check = grid[y - 1][x + 1] + grid[y][x] + grid[y + 1][x - 1]
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if word_to_check == 'MAS' or word_to_check == 'SAM':
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xmas_count += 1
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#print(word_to_check)
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print(xmas_count)
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