H, W = map(int, input().split())
S = [input() for _ in range(H)]

for i in range(H):
    S[i] = '.' + S[i] + '.'
S = ['.' * (W + 2)] + S + ['.' * (W + 2)]

if (H == 1) and (W == 1):
    print('Yes')
else:
    cnt_list = []
    for i in range(1,H+1):
        for j in range(1, W+1):
            if S[i][j] == '.':
                cnt_list.append(1)
            else:
                ser = S[i-1][j] + S[i][j-1] + S[i][j+1] + S[i+1][j] + S[i+1][j+1]
                cnt_list.append(ser.count('#'))
    if 0 in cnt_list:
        print('No')
    else:
        print('Yes')