#include <iostream>
#include <vector>
#include <queue>
#include <climits>
using namespace std;

struct sttr {
    int x, y;
    int time;
    sttr(int _x, int _y, int _t) : x(_x), y(_y), time(_t) {}
};

int main() {
    int t, x, y;
    cin >> t >> x >> y;
    vector<string> grid(y);
    sttr start(-1, -1, 0), end(-1, -1, 0);
    for (int i = 0; i < y; ++i) {
        cin >> grid[i];
        for (int j = 0; j < x; ++j) 
            if (grid[i][j] == 's') start = sttr(j, i, 0);
            else if (grid[i][j] == 'm') end = sttr(j, i, 0);        
    }
    if (start.x == -1 || end.x == -1) {
        cout << "55555" << endl;
        return 0;
    }
    const int dx[] = {0, 0, -1, 1};
    const int dy[] = {-1, 1, 0, 0};
    vector<vector<int>> vv(y, vector<int>(x, INT_MAX));
    vv[start.y][start.x] = 0;
    queue<sttr> q;
    q.push(start);
    while (!q.empty()) {
        sttr str = q.front();
        q.pop();
        if (str.x == end.x && str.y == end.y) {
            if (str.time <= t) cout << str.time << endl;
             else cout << "55555" << endl;
            return 0;
        }
        for (int i = 0; i < 4; ++i) {
            int nx = str.x + dx[i];
            int ny = str.y + dy[i];
            if (nx >= 0 && nx < x && ny >= 0 && ny < y && grid[ny][nx] != 'o') {
                int new_time = str.time;
                if (grid[ny][nx] == '.') 
                    new_time += 1;
                 else if (grid[ny][nx] == '#') new_time += 2;
                 else if (grid[ny][nx] == 'm') new_time += 1; 
                if (new_time < vv[ny][nx]) {
                    vv[ny][nx] = new_time;
                    q.push(sttr(nx, ny, new_time));
                }
            }
        }
    }
    cout << "55555";
}