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

int main()
{
    int n, m;
    cin >> n >> m;
    char mat[n][m];
    int si, sj; // poleto S
    int ei, ej; // poleto E
    for(int i = 0; i < n; i++) {
        for(int j = 0; j < m; j++) {
            cin >> mat[i][j];
            if(mat[i][j] == 'S') {
                si = i;
                sj = j;
            }
            if(mat[i][j] == 'E') {
                ei = i;
                ej = j;
            }
        }
    }
    bool visited[n][m];
    for(int i = 0; i < n; i++) {
        for(int j = 0; j < m; j++) {
            visited[i][j] = false;
        }
    }
    queue<int> q;
    q.push(si);
    q.push(sj);
    q.push(0);
    visited[si][sj] = true;
    int di[] = {-1, 1, 0, 0};
    int dj[] = {0, 0, -1, 1};
    while(!q.empty()) {
        int ci = q.front();
        q.pop();
        int cj = q.front();
        q.pop();
        int dist = q.front();
        q.pop();
        if(mat[ci][cj] == 'E') {
            cout << dist << endl;
            return 0;
        }
        for(int k = 0; k < 4; k++) {
            int ti = ci + di[k];
            int tj = cj + dj[k];
            if(ti >= 0 and ti < n and tj >= 0 and tj < m and mat[ti][tj] != '#' and !visited[ti][tj]) {
                visited[ti][tj] = true;
                q.push(ti);
                q.push(tj);
                q.push(dist + 1);
            }
        }
    }
    int dist_from_S_to_each_wall[n][m];
    for(int i = 0; i < n; i++) {
        for(int j = 0; j < m; j++) {
            dist_from_S_to_each_wall[i][j] = -1;
            visited[i][j] = false;
        }
    }
    q.push(si);
    q.push(sj);
    q.push(0);
    visited[si][sj] = true;
    while(!q.empty()) {
        int ci = q.front();
        q.pop();
        int cj = q.front();
        q.pop();
        int dist = q.front();
        q.pop();
        if(mat[ci][cj] == '#') {
            dist_from_S_to_each_wall[ci][cj] = dist;
            continue;
        }
        for(int k = 0; k < 4; k++) {
            int ti = ci + di[k];
            int tj = cj + dj[k];
            if(ti >= 0 and ti < n and tj >= 0 and tj < m and !visited[ti][tj]) {
                visited[ti][tj] = true;
                q.push(ti);
                q.push(tj);
                q.push(dist + 1);
            }
        }
    }
    int dist_from_E_to_each_wall[n][m];
    for(int i = 0; i < n; i++) {
        for(int j = 0; j < m; j++) {
            dist_from_E_to_each_wall[i][j] = -1;
            visited[i][j] = false;
        }
    }
    q.push(ei);
    q.push(ej);
    q.push(0);
    visited[ei][ej] = true;
    while(!q.empty()) {
        int ci = q.front();
        q.pop();
        int cj = q.front();
        q.pop();
        int dist = q.front();
        q.pop();
        if(mat[ci][cj] == '#') {
            dist_from_E_to_each_wall[ci][cj] = dist;
            continue;
        }
        for(int k = 0; k < 4; k++) {
            int ti = ci + di[k];
            int tj = cj + dj[k];
            if(ti >= 0 and ti < n and tj >= 0 and tj < m and !visited[ti][tj]) {
                visited[ti][tj] = true;
                q.push(ti);
                q.push(tj);
                q.push(dist + 1);
            }
        }
    }
    int rezultat = -1;
    for(int i = 0; i < n; i++) {
        for(int j = 0; j < m; j++) {
            if(mat[i][j] == '#') {
                if(dist_from_S_to_each_wall[i][j] != -1 and dist_from_E_to_each_wall[i][j] != -1) {
                    rezultat = max(rezultat, dist_from_S_to_each_wall[i][j] + dist_from_E_to_each_wall[i][j]);
                }
            }
        }
    }
    cout << rezultat << endl;
    return 0;
}
/*
 4 5
 S..#E
 ###..
 #....
 .....
 */