#include <bits/stdc++.h>
using namespace std;

#define rep(i, a, b) for (int i = (int)(a); i < (int)(b); i++)
#define rrep(i, a, b) for (int i = (int)(a); i > (int)(b); i--)
#define ll long long
#define all(x) x.begin(), x.end()
#define rall(x) x.rbegin(), x.rend()
#define PQ priority_queue<int, vector<int>, greater<int>>
#define PQ_g priority_queue<pair<ll, int>, vector<pair<ll, int>>, greater<pair<ll, int>>>
#define chmin(a, b) a = min(a, b)
#define chmax(a, b) a = max(a, b)
const int d4[4][2] = {{0, 1}, {1, 0}, {0, -1}, {-1, 0}};
const int d8[8][2] = {{0, 1}, {1, 1}, {1, 0}, {1, -1}, {0, -1}, {-1, -1}, {-1, 0}, {-1, 1}};
void Yes(bool b) {cout << (b ? "Yes" : "No") << endl;}

int main() {
    int h, w; cin >> h >> w;
    vector<string> C(h);
    rep(i, 0, h) cin >> C[i];
    
    queue<pair<int, int>> Q;
    vector<vector<int>> dist_s(h, vector<int> (w, 1 << 30));
    vector<vector<int>> dist_g(h, vector<int> (w, 1 << 30));
    vector<vector<bool>> visited_s(h, vector<bool> (w));
    vector<vector<bool>> visited_g(h, vector<bool> (w));

    auto can_go = [&](int x, int y) -> bool{
        return 0 <= x && x < h && 0 <= y && y < w && C[x][y] != '#';
    };

    Q.push(make_pair(0, 0));
    dist_s[0][0] = 0;

    while (!Q.empty()) {
        int posx = Q.front().first;
        int posy = Q.front().second;
        Q.pop();
        if (visited_s[posx][posy]) continue;
        visited_s[posx][posy] = true;
        const int d2[2][2] = {{0, 1}, {1, 0}};
        for (auto &to: d2) {
            int next_x = posx + to[0];
            int next_y = posy + to[1];
            if (can_go(next_x, next_y) && !visited_s[next_x][next_y]) {
                dist_s[next_x][next_y] = min(dist_s[next_x][next_y], dist_s[posx][posy] + 1);
                Q.push(make_pair(next_x, next_y));
            }
        }
    }

    Q.push(make_pair(h - 1, w - 1));
    dist_g[h - 1][w - 1] = 0;

    while (!Q.empty()) {
        int posx = Q.front().first;
        int posy = Q.front().second;
        Q.pop();
        if (visited_g[posx][posy]) continue;
        visited_g[posx][posy] = true;
        const int d2[2][2] = {{0, -1}, {-1, 0}};
        for (auto &to: d2) {
            int next_x = posx + to[0];
            int next_y = posy + to[1];
            if (can_go(next_x, next_y) && !visited_g[next_x][next_y]) {
                dist_g[next_x][next_y] = min(dist_g[next_x][next_y], dist_g[posx][posy] + 1);
                Q.push(make_pair(next_x, next_y));
            }
        }
    }
    
    if (visited_s[h - 1][w - 1]) {
        cout << dist_s[h - 1][w - 1] << endl;
    } else {
        bool flg = false;
        rep(i, 0, h - 1) {
            bool have_s = false;
            rep(j, 0, w) {
                if (visited_s[i][j]) have_s = true;
                if (visited_g[i + 1][j] && have_s) {
                    flg = true;
                    break;
                }
            }
            if (flg) break;
        }

        rep(j, 0, w - 1) {
            bool have_s = false;
            rep(i, 0, h) {
                if (visited_s[i][j]) have_s = true;
                if (visited_g[i][j + 1] && have_s) {
                    flg = true;
                    break;
                }
            }
            if (flg) break;
        }
        
        cout << (flg ? (h + w - 1) : (h + w)) << endl;
    }
}