77 lines
1.7 KiB
Python
77 lines
1.7 KiB
Python
import itertools
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def scan_line(line):
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to_find = "XMAS"
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return line.count(to_find)
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def transpose(list_2d):
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outlist = []
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for j in range(max(map(len, list_2d))):
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outlist.append([])
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for i in range(len(list_2d)):
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# TODO: This is a weird edge case.
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if j < len(list_2d[i]):
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outlist[j].append(list_2d[i][j])
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outlist[j] = "".join(outlist[j])
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return outlist
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def rotate(list_2d):
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x_max, y_max = len(list_2d), len(list_2d[0])
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diagonal_list = []
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# Diagonals starting from (0,0), for the first row.
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for i in range(x_max):
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substring = ""
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x = i
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y = 0
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while x < x_max and y < y_max:
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#print(x, x_max, y, y_max)
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substring += list_2d[x][y]
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x += 1
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y += 1
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diagonal_list.append(substring)
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# Reverse
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diagonal_list = diagonal_list[::-1]
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# Diagonals starting from (0,1), for the first column.
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for j in range(1, y_max):
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substring = ""
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x = 0
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y = j
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while x < x_max and y < len(list_2d[x]):
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substring += list_2d[x][y]
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x += 1
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y += 1
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diagonal_list.append(substring)
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return diagonal_list
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if __name__ == "__main__":
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result = 0
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with open("input", "r") as fp:
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# Skip last line as it is empty
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full_string = fp.read().split("\n")[:-1]
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for line in full_string:
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result += scan_line(line)
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result += scan_line(line[::-1])
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for line in transpose(full_string):
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result += scan_line(line)
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result += scan_line(line[::-1])
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diagonal_list = rotate(full_string)
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for line in full_string:
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result += scan_line(line)
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result += scan_line(line[::-1])
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# TODO: Transposion after rotating is ill-defined.
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for line in transpose(rotate(full_string)):
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result += scan_line(line)
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result += scan_line(line[::-1])
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#transposed_file =
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print(f"The sum of all horizontal XMAS's equals {result}.")
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