rt

#include<algorithm>
#include<iostream>
#include<cstring>
#include<cstdlib>
#include<iomanip>
#include<cstdio>
#include<ctime>
#include<cmath>
#include<map>
using namespace std;
int a[101][101];
char c;
int n,m;
int next[4][2]={{0,1},{1,0},{0,-1},{-1,0}};
int minn=99999;
int flag;

int book[101][101];
void dfs(int x,int y){
	int nextx=1,nexty=1;
	if(x==n&&y==m){
		cout<<"Yes"<<endl;
		flag=1;
	}
	if(flag==1) return;
	for(int k=0;k<=3;k++){
		nextx=x+next[k][0];
		nexty=y+next[k][1];
		if(nextx<1||nextx>n||nexty<1||nexty>m) continue; 
		if(a[nextx][nexty]==0&&book[nextx][nexty]==0){
			book[nextx][nexty]=1;
			dfs(nextx,nexty);
			book[nextx][nexty]=0;
		}
	}
	return;
}
int main(){
	book[1][1]=1;
	cin>>n>>m;
	for(int i=1;i<=n;i++){
		for(int j=1;j<=m;j++){
			cin>>c;
			if(c=='#') a[i][j]=1;
		}
	}
	dfs(1,1);
	if(flag==0) cout<<"No"<<endl;
	return 0;
}

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