#include <iostream>
#include <queue>
#include <tuple>
using namespace std;

#define REP(i,a,b) for(int i=a;i<(int)b;i++)
#define rep(i,n) REP(i,0,n)

typedef long long ll;

int W, H;
char G[22][22];
int dist[22][22];

int dx[4] = {-1,0,1,0};
int dy[4] = {0,-1,0,1};

inline bool valid(int x, int y) {
  return 0<=x&&x<W && 0<=y&&y<H;
}

int main() {

  int sx, sy;
  cin >> W >> H;
  rep(i, H) rep(j, W) {
    cin >> G[i][j];
    if(G[i][j] == '.') { sx = j, sy = i; }
  }

  std::queue<std::tuple<int, int>> q;
  q.emplace(sx, sy);
  rep(i, 22) rep(j, 22) dist[i][j] = 1<<29;
  dist[sy][sx] = 0;
  while(!q.empty()) {
    int x = std::get<0>(q.front());
    int y = std::get<1>(q.front());
    q.pop();
    rep(k, 4) {
      int nx = x+dx[k], ny = y+dy[k];
      if(!valid(nx, ny)) { continue; }
      int nc = dist[y][x]+(G[ny][nx]=='#');
      if(dist[ny][nx] <= nc) { continue; }
      dist[ny][nx] = nc;
      q.emplace(nx, ny);
    }
  }

  rep(i, H) rep(j, W) {
    if(G[i][j] == '.' && dist[i][j]) {
      cout << dist[i][j] << endl;
      return 0;
    }
  }

  return 0;
}