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: cont = [list(i.strip()) for i in open("day4input.txt").readlines()]
  
  def get_neighbors(matrix, x, y):
      rows = len(matrix)
      cols = len(matrix[0])
      neighbors = []
  
      directions = [(-1, -1), (-1, 0), (-1, 1), (0, -1), (0,0), (0, 1), (1, -1), (1, 0), (1, 1)]
      
      for dx, dy in directions:
          nx, ny = x + dx, y + dy
          if 0 <= nx < rows and 0 <= ny < cols:
              neighbors.append(matrix[nx][ny])
      
      return neighbors
  
  def check(matrix):
      ret = 0
      m = matrix.copy()
      mas = ["MAS", "SAM"]
      d = ''.join([m[0][0], m[1][1], m[2][2]])
      a = ''.join([m[0][2], m[1][1], m[2][0]])
      ret += 1 if (d in mas and a in mas) else 0
      return ret
  
  t = 0
  
  for x in range(len(cont)):
      for y in range(len(cont[x])):
          if x in [0, 139] or y in [0, 139]:
              continue
          if cont[x][y] == "A":
              neighbours = get_neighbors(cont, x,y)
              matrix = [neighbours[:3], neighbours[3:6], neighbours[6:]]
  
              t += check(matrix) 
  
  print(t)
  