question: --- Day 4: Ceres Search ---
  
  "Looks like the Chief's not here. Next!" One of The Historians pulls out a device and pushes the only button on it. After a brief flash, you recognize the interior of the Ceres monitoring station!
  
  As the search for the Chief continues, a small Elf who lives on the station tugs on your shirt; she'd like to know if you could help her with her word search (your puzzle input). She only has to find one word: XMAS.
  
  This word search allows words to be horizontal, vertical, diagonal, written backwards, or even overlapping other words. It's a little unusual, though, as you don't merely need to find one instance of XMAS - you need to find all of them. Here are a few ways XMAS might appear, where irrelevant characters have been replaced with .:
  
  ..X...
  .SAMX.
  .A..A.
  XMAS.S
  .X....
  The actual word search will be full of letters instead. For example:
  
  MMMSXXMASM
  MSAMXMSMSA
  AMXSXMAAMM
  MSAMASMSMX
  XMASAMXAMM
  XXAMMXXAMA
  SMSMSASXSS
  SAXAMASAAA
  MAMMMXMMMM
  MXMXAXMASX
  In this word search, XMAS occurs a total of 18 times; here's the same word search again, but where letters not involved in any XMAS have been replaced with .:
  
  ....XXMAS.
  .SAMXMS...
  ...S..A...
  ..A.A.MS.X
  XMASAMX.MM
  X.....XA.A
  S.S.S.S.SS
  .A.A.A.A.A
  ..M.M.M.MM
  .X.X.XMASX
  Take a look at the little Elf's word search. How many times does XMAS appear?
  
  Your puzzle answer was 2434.
  
  --- Part Two ---
  
  The Elf looks quizzically at you. Did you misunderstand the assignment?
  
  Looking for the instructions, you flip over the word search to find that this isn't actually an XMAS puzzle; it's an X-MAS puzzle in which you're supposed to find two MAS in the shape of an X. One way to achieve that is like this:
  
  M.S
  .A.
  M.S
  Irrelevant characters have again been replaced with . in the above diagram. Within the X, each MAS can be written forwards or backwards.
  
  Here's the same example from before, but this time all of the X-MASes have been kept instead:
  
  .M.S......
  ..A..MSMS.
  .M.S.MAA..
  ..A.ASMSM.
  .M.S.M....
  ..........
  S.S.S.S.S.
  .A.A.A.A..
  M.M.M.M.M.
  ..........
  In this example, an X-MAS appears 9 times.
  
  Flip the word search from the instructions back over to the word search side and try again. How many times does an X-MAS appear?
solution: FNAME = "data.txt"
  WORD = "MMASS"
  
  
  def main():
      matrix = file_to_matrix(FNAME)
      print(count_word(matrix, WORD))
  
  def file_to_matrix(fname: str) -> list[list]:
      out = []
      fopen = open(fname, "r")
      for line in fopen:
          out.append([c for c in line if c != "\n"])
      return out
  
  def count_word(matrix: list[list], word) -> int:
      count = 0
      len_matrix = len(matrix)
      for i in range(len_matrix):
          for j in range(len_matrix):
              count += count_word_for_pos(matrix, (i,j), word)
  
      return count
  
  def count_word_for_pos(matrix: list[list], pos: tuple[int, int], word: str) -> int:
      count = 0
      if pos[0] < 1 or pos[0] > len(matrix)-2 or pos[1] < 1 or pos[1] > len(matrix)-2:
          return 0
      patterns = [[(-1,-1),(1,-1),(0,0),(-1,1),(1,1)],
                  [(1,1),(-1,1),(0,0),(1,-1),(-1,-1)],
                  [(-1,-1),(-1,1),(0,0),(1,-1),(1,1)],
                  [(1,1),(1,-1),(0,0),(-1,1),(-1,-1)],]
      for pattern in patterns:
          s = "".join([matrix[pos[0]+p[0]][pos[1]+p[1]] for p in pattern])
          if s == word:
              return 1
  
      return count
  
  if __name__ == "__main__":
      main()