#include<bits/stdc++.h>
using namespace std;
int n,m,vis[105][105];
char a[105][105];
bool flag=true;
void dfs(int x,int y)
{
    vis[x][y]=1;
    if(x==n&&y==m)
    {
        cout<<"Yes";
        flag=false;
        return;
    }
    if(a[x+1][y]=='.'&&vis[x+1][y]==0)
        dfs(x+1,y);
    else if(a[x][y+1]=='.'&&vis[x][y+1]==0)
        dfs(x,y+1);
    else if(a[x][y-1]=='.'&&vis[x][y-1]==0)
        dfs(x,y-1); 
    else if(a[x-1][y]=='.'&&vis[x-1][y]==0)
        dfs(x-1,y);
    if(x==1&&y==1&&flag)
        cout<<"No";
}
int main()
{
    cin>>n>>m;
    for(int i=1;i<=n;i++)
        for(int j=1;j<=m;j++)
            cin>>a[i][j];
    dfs(1,1);
}