#include <bits/stdc++.h>
#pragma GCC optimize("Ofast")
#pragma GCC optimize("unroll-loops")
using namespace std;
using std::cout;
using std::cin;
using std::endl;
using ll=long long;
using ld=long double;
const ll ILL=2167167167167167167;
const int INF=2100000000;
const int mod=998244353;
#define rep(i,a,b) for (int i=(int)(a);i<(int)(b);i++)
#define all(p) p.begin(),p.end()
template<class T> using _pq = priority_queue<T, vector<T>, greater<T>>;
template<class T> ll LB(vector<T> &v,T a){return lower_bound(v.begin(),v.end(),a)-v.begin();}
template<class T> ll UB(vector<T> &v,T a){return upper_bound(v.begin(),v.end(),a)-v.begin();}
template<class T> bool chmin(T &a,const T &b){if(a>b){a=b;return 1;}else return 0;}
template<class T> bool chmax(T &a,const T &b){if(a<b){a=b;return 1;}else return 0;}
template<class T> void So(vector<T> &v) {sort(v.begin(),v.end());}
template<class T> void Sore(vector<T> &v) {sort(v.begin(),v.end(),[](T x,T y){return x>y;});}
void yneos(bool a){if(a) cout<<"Yes\n"; else cout<<"No\n";}
template<class T> void vec_out(vector<T> &p){for(int i=0;i<(int)(p.size());i++){if(i) cout<<" ";cout<<p[i];}cout<<"\n";}
template<class T> T vec_min(vector<T> &a){assert(!a.empty());T ans=a[0];for(auto &x:a) chmin(ans,x);return ans;}
template<class T> T vec_max(vector<T> &a){assert(!a.empty());T ans=a[0];for(auto &x:a) chmax(ans,x);return ans;}
template<class T> T vec_sum(vector<T> &a){assert(!a.empty());T ans=a[0]-a[0];for(auto &x:a) ans+=x;return ans;}
int pop_count(long long a){int res=0;while(a){res+=(a&1),a>>=1;}return res;}



void solve();
// oddloop
int main() {
	ios::sync_with_stdio(false);
	cin.tie(nullptr);
	
	int t=1;
	//cin>>t;
	rep(i,0,t) solve();
}

void solve(){
	int H,W;
	cin>>H>>W;
	vector<string> p(H);
	rep(i,0,H) cin>>p[i];
	vector<vector<int>> q(H,vector<int>(W));
	rep(i,1,H-1) rep(j,1,W-1) rep(k,-1,2) rep(l,-1,2) if(p[i+k][j+l]=='#') q[i][j]=1;
	rep(i,0,H) rep(j,0,W){
		if(i==0||j==0||i==H-1||j==W-1) q[i][j]=1;
	}
	int ans=2;
	rep(a,0,H) rep(b,0,W){
		vector<pair<int,int>> order;
		vector seen(H,vector<int>(W,INF));
		order.push_back({1,1});
		seen[1][1]=0;
		int val=1;
		auto r=q;
		if(q[a][b]) val=0;
		else{
			int ban=0;
			rep(i,0,3) rep(j,0,3){
				if(i==a&&b==j) ban=1;
				if(i+a==H-1&&j+b==W-1) ban=1;
			}
			if(ban==0){
				rep(i,-1,2) rep(j,-1,2){
					r[i+a][j+b]=1;
				}
			}
		}
		vector<int> dx={0,0,1,-1,1,1,-1,-1},dy={1,-1,0,-1,1,-1,1,-1};
		rep(i,0,(int)order.size()){
			auto [x,y]=order[i];
			rep(k,0,dx.size()){
				auto s=x+dx[k],t=y+dy[k];
				if(r[s][t]) continue;
				else if(chmin(seen[s][t],0))  order.push_back({s,t});
			}
		}
		if(seen[H-2][W-2]) chmin(ans,val);
	}
	cout<<ans<<"\n";
}