tate, yoko = map(int, input().split())
s  = [input()  for i in range(tate)]
dxy = [(-1, -1), (-1, 0), (-1, 1), (0, -1), (0, 1), (1, -1), (1, 0), (1, 1)]
for i in range(tate):
    for j in range(yoko):
        if s[i][j] == "#":
            save = []
            for dx, dy in dxy:
                if i + dy < 0 or i + dy > tate - 1 or j + dx < 0 or j + dx > yoko - 1: continue
                if s[i + dy][j + dx] == "#": 
                    save.append("#")
                    break
            if "#" in save: continue
            else:
                print("No")
                exit()
print("Yes")