#include<bits/stdc++.h>
using namespace std;
char x[101][101];
int x2[101][101]={};
bool iffi=0;
void bds(int x1,int y,int n,int m){
	if(x[x1][y]=='#')
	{
		return ;
	}
	else if(x1==m&&y==n&&iffi==0)
	{
		cout<<"Yes";
		iffi=1;
		return;
	}
	x2[x1][y]=1;
	if(x1!=1&&x2[x1-1][y]==0)
	{
		bds(x1-1,y,n,m);
	}
	if(y!=1&&x2[x1][y-1]==0)
	{
		bds(x1,y-1,n,m);
	}
	if(x1!=n&&x2[x1+1][y]==0)bds(x1+1,y,n,m);
	if(y!=n&&x2[x1][y+1]==0)bds(x1,y+1,n,m);
}
int main()
{
    int n,m;
    cin>>n>>m;
    for(int i=1;i<=n;i++)
    {
    	for(int i1=1;i1<=m;i1++)
    	{
    		cin>>x[i][i1];
		}
	}
	bds(1,1,m,n);
	if(iffi==0)cout<<"No";
	return 0;
}