#include<bits/stdc++.h>
using namespace std;
char mi[10100][10100];
int n,m;
bool vis[10100][10100],ok;
void dfs(int x,int y){
	
	if(mi[n][m]=='#') return;
	if(n<=1||m<=1) return;
	if(vis[x][y]) return;
	vis[x][y]=1;
	if(x==n&&y==m) ok=true;
	dfs(x+1,y);
	dfs(x-1,y);
	dfs(x,y+1);
	dfs(x,y-1);
	
	
	
	
}
int main(){
	
	cin>>n>>m;
	for(int i=1;i<=n;i++){
		for(int j=1;j<=m;j++){
			cin>>mi[i][j];
		}
	}
	dfs(1,1);
	if(ok){
		cout<<"Yes";
	}else{
		cout<<"No";
	}
}