output_description: If square1001 can achieve his objective, print `Yes`; if he cannot, print
  `No`.
  
  * * *
input_description: Input is given from Standard Input in the following format:
  
      
      
      H W
      s_{1, 1} s_{1, 2} s_{1, 3} ... s_{1, W}
      s_{2, 1} s_{2, 2} s_{2, 3} ... s_{2, W}
        :   :
      s_{H, 1} s_{H, 2} s_{H, 3} ... s_{H, W}
attempt: height,width = map(int, input().split())
  map_list = []
  for i in range(height):
      map_list.append(list(input()))
      map_list[i].append('0')
  map_list.append(['0'] * width)
  
  for h in range(height):
      for w in range(width):
          if map_list[h][w] == '#':
              if '#' in [map_list[h-1][w], map_list[h+1][w], map_list[h][w-1], map_list[h][w+1]]:
  
              else:
                  print("No")
                  exit()
  
  print("Yes")
  
problem_description: Statement
  
  We have a canvas divided into a grid with H rows and W columns. The square at
  the i-th row from the top and the j-th column from the left is represented as
  (i, j).  
  Initially, all the squares are white. square1001 wants to draw a picture with
  black paint. His specific objective is to make Square (i, j) black when s_{i,
  j}= `#`, and to make Square (i, j) white when s_{i, j}= `.`.  
  However, since he is not a good painter, he can only choose two squares that
  are horizontally or vertically adjacent and paint those squares black, for
  some number of times (possibly zero). He may choose squares that are already
  painted black, in which case the color of those squares remain black.  
  Determine if square1001 can achieve his objective.
samples: [{"input": "3 3\n    .#.\n    ###\n    .#.", "output": "Yes\n    \n\nOne possible way to achieve the objective is shown in the figure below. Here,\nthe squares being painted are marked by stars.\n\n![ ](https://img.atcoder.jp/abc096/18f94b6627ec5dc8aa4f6d99ae1c8fca.png)\n\n* * *"}, {"input": "5 5\n    #.#.#\n    .#.#.\n    #.#.#\n    .#.#.\n    #.#.#", "output": "No\n    \n\nsquare1001 cannot achieve his objective here.\n\n* * *"}, {"input": "11 11\n    ...#####...\n    .##.....##.\n    #..##.##..#\n    #..##.##..#\n    #.........#\n    #...###...#\n    .#########.\n    .#.#.#.#.#.\n    ##.#.#.#.##\n    ..##.#.##..\n    .##..#..##.", "output": "Yes"}]