#include<bits/stdc++.h>
using namespace std;
int  fx, fy, p=0;
char mp[110][110];
bool vist[110][110];
int ax[6]={-1, 0, 1, 0};
int ay[6]={0, 1, 0, -1};
void mg(int nx, int ny){
	int i;
	if(nx == fx && ny == fy){
		cout << "Yes";
		exit(0);
	}
	for(i = 0;i < 4;++i){
		
		int tx, ty;
		tx = nx + ax[i];
		ty = ny + ay[i];
		if(mp[tx][ty] == '#')continue;
		if(vist[tx][ty] == 1)continue;
		if(tx <= 0 || tx > fx || ty > fy || ty <= 0)continue;
		vist[tx][ty] = 1;
		mg(tx,ty);
		vist[tx][ty] = 0;
	}
	
}
int main(){
	cin >> fx >> fy;
	for(int i = 1;i <= fx; ++i){
		for(int j = 1; j <= fy; ++j){
			cin >> mp[i][j];
		}
	} 
	vist[1][1] = 1;
	mg(1, 1);
	cout << "No";
return 0;
}