#include <bits/stdc++.h>
using namespace std;
#define rep(i, x, limit) for (long long i = (long long)x; i < (long long)limit; i++)
#define REP(i, x, limit) for (long long i = (long long)x; i <= (long long)limit; i++)
#define all(x) x.begin(), x.end()
#define rall(x) x.rbegin(), x.rend()
#define el endl
#define spa " "
#define Yes cout << "Yes" << el
#define No cout << "No" << el
#define YES cout << "YES" << el
#define NO cout << "NO" << el
#define inp(x) for(auto &i:x)cin>>i
#define eps (1e-10)
#define Equals(a,b) (fabs((a) - (b)) < eps )
#define debug(x) cerr << #x << " = " << x << el
using ll = long long;
using ull = unsigned long long;
using pii = pair<int,int>;
using pll = pair<ll,ll>;
using vi = vector<int>;
using vl = vector<ll>;
using vvl = vector<vector<ll>>;
using vs = vector<string>;
using vb = vector<bool>;
const double pi = 3.141592653589793238;
const int inf = 1073741823;
const ll infl = 1LL << 60;
const string ABC = "ABCDEFGHIJKLMNOPQRSTUVWXYZ";
const string abc = "abcdefghijklmnopqrstuvwxyz";
const ll MOD = 998244353;
#include<atcoder/all>
using namespace atcoder;
using mint = modint998244353;
using vm = vector<mint>;

int main() {
  ios::sync_with_stdio(false);
  cin.tie(nullptr);
  ll h,w;cin>>h>>w;
  vs S(h);inp(S);
  vvl dp(h,vl(w,0));
  dp[0][0] = 1;
  queue<pll> que;
  que.push({0,0});
  auto ok=[&](ll x,ll y){
    if(x<0||h<=x||y<0||w<=y)return false;
    if(S[x][y]=='#')return false;
    return true;
  };
  ll h1=0,w1=0,h2=h-1,w2=w-1;
  while(!que.empty()){
    auto [x,y]=que.front();que.pop();
    h1=max(h1,x);
    w1=max(w1,y);
    for(auto [dx,dy]:vector<pll>{{1,0},{0,1}}){
      ll nx=x+dx,ny=y+dy;
      if(!ok(nx,ny))continue;
      if(dp[nx][ny]==0)que.push({nx,ny});
      dp[nx][ny]=1;
    }
  }
  ll ans=h+w-2;
  if(dp[h-1][w-1]==1){
    cout<<ans<<el;
    return 0;
  }
  dp.assign(h,vl(w,0));
  que.push({h-1,w-1});
  while(!que.empty()){
    auto [x,y]=que.front();que.pop();
    h2=min(h2,x);
    w2=min(w2,y);
    for(auto [dx,dy]:vector<pll>{{-1,0},{0,-1}}){
      ll nx=x+dx,ny=y+dy;
      if(!ok(nx,ny))continue;
      if(dp[nx][ny]==0)que.push({nx,ny});
      dp[nx][ny]=1;
    }
  }
  if(h2-1<=h1||w2-1<=w1)ans++;
  else ans+=2;
  cout<<ans<<el;
}