我累个骚刚

/*
BUG:
39 29
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*/


#include<bits/stdc++.h>
using namespace std;
int walk[8][2]={{1,0},{-1,0},{0,1},{0,-1}/*,{1,1},{-1,1},{-1,-1},{1,-1}*/};
string mp[50];
int n,m;
struct node{
	int x,y,steps;
};
bool vis[50][50];
bool check(node x){
	return x.x>=0 && x.x<n && x.y>=0 && x.y<m && mp[x.x][x.y]=='.' && !vis[x.x][x.y];
}
int ans=0;
int Depth_first_search(node start,node end){
	queue<node> q;
	q.push(start);
	while(q.size()){
		node f=q.front();
		q.pop();
        vis[f.x][f.y]=1;
		if(f.x==end.x && f.y==end.y) return f.steps;
		for(int i=0;i<4;i++){
			int nextx=f.x+walk[i][0];
			int nexty=f.y+walk[i][1];
			node next={nextx,nexty,f.steps+1};
			if(check(next)){
                vis[next.x][next.y]=1;
				q.push(next);
			}
		}
	}
}
int main(){
	cin>>n>>m;
	for(int i=0;i<n;i++){
		cin>>mp[i];
	}
	cout<<Depth_first_search({0,0,1},{n-1,m-1});
	return 0;
}