RT

#include <iostream>

using namespace std;

int n, m; // n是y！！！m是x！！！
bool map[110][110], run[110][110], flag; // map为地图，0为无墙，1为有墙
// run为是否用过

bool hf(int x, int y) {
	if (x >= m || x < 0 || y >= n || y < 0 || run[x][y] || map[x][y]) {
		return 0;
	}
	return 1;
}


void dfs(int x, int y) {
	if (flag) {
		return;
	}
	if (x == m - 1 && y == n - 1) {
		flag = 1;
		return;
	}
	for (int i = -1; i <= 1; i += 1) {
		for (int j = -1; j <= 1; j += 1) {
			if (hf(x + i, y + j)) {
				run[x + i][y + j] = 1;
				dfs(x + i, y + j);
			}
		}
	}
}


int main() {
	cin >> n >> m;
	char tmp;
	for (int i = 0; i < m; i++) {
		for (int j = 0; j < n; j++) {
			cin >> tmp;
			if (tmp == '#') {
				map[i][j] = 1;
			} else {
				map[i][j] = 0;
			}
		}
	}
	dfs(0, 0);
	if (flag) {
		cout << "Yes" << endl;
		return 0;
	}
	cout << "No" << endl;
}