#include <bits/stdc++.h>
using namespace std;
const int mod = 1000000007;
int main() {
  ios::sync_with_stdio(false);
  int h, w;
  cin >> h >> w;
  string s[h + 2][w + 2];
  for (int i = 0; i <= h + 1; i++)
    for (int j = 0; j <= w + 1; j++) cin >> s[i][j];
  for (int i = 1; i <= h; i++)
    for (int j = 1; j <= w; j++) cin >> s[i][j];
  for (int i = 1; i <= h; i++) {
    for (int j = 1; j <= w; j++) {
      if (s[i][j] == "#" && s[i][j] != s[i - 1][j] && s[i][j] != s[i][j - 1] &&
          s[i][j] != s[i][j + 1] && s[i][j] != s[i + 1][j]) {
        cout << "No";
        return 0;
      }
    }
  }
  cout << "Yes";
}
