#include<iostream>
#include<string>
#include<queue>
using namespace std;
const int BUF = 25;
const int INF = 1<<20;


class QData{
public:
    int r, c, cost;
    QData(){}
    QData(int r, int c, int cost):
        r(r), c(c), cost(cost){}

    bool operator< (const QData &opp) const {
        return cost > opp.cost;
    }
};


int row, col;
string b[BUF];

void read() {
    cin >> col >> row;
    for (int i = 0; i < row; ++i)
        cin >> b[i];
}


void work() {
    priority_queue<QData> Q;
    int cost[BUF][BUF];
    
    for (int i = 0; i < BUF; ++i)
        for (int j = 0; j < BUF; ++j)
            cost[i][j] = INF;
    
    for (int i = 0; i < row; ++i)
        for (int j = 0; j < col; ++j) {
            if (b[i][j] == '.') {
                cost[i][j] = 0;
                Q.push(QData(i, j, 0));
                goto _finish;
            }
        }
    
 _finish:

    const int dr[] = {-1, 0, 1, 0};
    const int dc[] = {0, 1, 0, -1};
    
    while (!Q.empty()) {
        QData curr = Q.top();
        Q.pop();

        if (curr.cost > 0 && b[curr.r][curr.c] == '.') {
            cout << curr.cost << endl;
            break;
        }
        
        for (int i = 0; i < 4; ++i) {
            int nr = curr.r + dr[i];
            int nc = curr.c + dc[i];
            
            if (!(0 <= nr && nr < row && 0 <= nc && nc < col))
                continue;
            
            int nexCost = curr.cost + (b[nr][nc] != '.');
            
            if (cost[nr][nc] > nexCost) {
                cost[nr][nc] = nexCost;
                Q.push(QData(nr, nc, nexCost));
            }
        }
    }
}


int main() {
    read();
    work();
    return 0;
}