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

using ll = long long int;
using P = pair<int,int>;
using P3 = pair<ll,P>;
using PP = pair<P, P>;
constexpr int INF = 1<<30;
constexpr ll MOD = (1e9)+7;
constexpr int di[] = {0,1,0,-1};
constexpr int dj[] = {1,0,-1,0};

int main(){
    int h, w;
    cin >> h >> w;
    vector<string> s(h);
    for(int i=0;i<h;i++){
        cin >> s[i];
    }
    vector<vector<ll> > d(h, vector<ll>(w, INF));
    d[0][0] = 0;
    priority_queue<P3,vector<P3>,greater<P3> > que;
    que.push(make_pair(0LL,P(0,0)));
    while(!que.empty()){
        auto p = que.top();
        que.pop();
        int i = p.second.first, j = p.second.second;
        if(d[i][j] < p.first) continue;
        for(int k=0;k<2;k++){
            int ni = i+di[k], nj=j+dj[k];
            if(ni<0||ni>=h)continue;
            if(nj<0||nj>=w)continue;
            ll nd;
            if(s[ni][nj] == '.'){
                nd = d[i][j] + 1;
            }else{
                nd = d[i][j] + 1 + ni + nj;
            }
            if(d[ni][nj] > nd){
                d[ni][nj] = nd;
                que.push(make_pair(d[ni][nj],P(ni,nj)));
            }
        }
    }
    cout << d[h-1][w-1] << endl;
    return 0;
}