h , w = (int(i) for i in input().split())
a =[]
dy = [0, 0, 1, -1]
dx = [1, -1, 0, 0]


for i in range(w):
    a.append(input())
    
f = True
def check(x,y):
    if a[x][y] =='.':
        return True
    for n in range(4):
        i = dx[n]
        j = dy[n]
        if 0 <= x+i < h and 0 <= y + j < w and a[x+i][y+j]=='#':
            #print(x+i,y+j)
            return True
        return False

print(check(0,0))
f = True
for i in range(w):
    for j in range(h):
        l = check(i,j)
        if not(l) and f:
                print ("No")
                f = False
                
if(f):
    print("Yes")