new_contents: row_list = [40, 400000]
  for rows in row_list:
      curr = '.^^^^^.^^^..^^^^^...^.^..^^^.^^....^.^...^^^...^^^^..^...^...^^.^.^.......^..^^...^.^.^^..^^^^^...^.'
      width = len(curr)
      safe_tiles = curr.count(".")
      left = rows-1
  
      while left != 0:
          prev = "".join([".", curr, "."])
          new_curr = []
          for i in range(width):
              check = prev[i:i + 3]
              new_tile = "." if check[0] == check[2] else "^"
              new_curr.append(new_tile)
          curr = "".join(new_curr)
          safe_tiles += curr.count(".")
          left -= 1
  
      print("{} safe tiles in {} rows".format(safe_tiles, rows))
      
  
subject: Create day_18_part_1+2.py