using System;
class Program
{
	static void Main()
  {
	string[] input = Console.ReadLine().Split(' ');
	int h = int.Parse(input[0]);
	int w = int.Parse(input[1]);
    string[] masu = new string[h];//入力マスを受け取る
    int result = 1;
	for(int i = 0; i < h; i++)
        {
          masu[i] = Console.ReadLine();	
        }
      
       
        for(int i = 0; i < h; i++)
        {
          for(int j = 0; j < w; j++)
          {
          	if(masu[i][j] == '#')
            {
              result = 1;
            if((i-1 < 0 || masu[i-1][j] == '#')||
              (i+1 > h || masu[i+1][j] == '#')||
              (j-1 < 0 || masu[i][j-1] == '#')||
              (j+1 > w || masu[i][j+1] == '#'))
              result = 0;
            }
                  
                
       	  }
          
          
        }
      Console.WriteLine((result == 1) ? "YES" : "NO");
  }
  
}