#include 
#include 
#include 
using namespace std;

int main() {
    int redovi, koloni;
    cin >> redovi >> koloni;
    
    char lavirint[redovi][koloni];
    int poseteno[redovi][koloni];
    
    int sashe[redovi][koloni]; // ni kazuva dali mozeme da stigneme od kukjata na sashe do ova pole i vo kolku cekori
    int elena[redovi][koloni];
    
    for(int i = 0; i < redovi; i++) {
        for(int j = 0; j < koloni; j++) {
            sashe[i][j] = -1;
            elena[i][j] = -1;
        }
    }
    int si, sj; // kaj se naoga kukjata na sashe
    int ei, ej; // kaj se naoga kukjata na elena
    for(int i = 0; i < redovi; i++) {
        for(int j = 0; j < koloni; j++) {
            cin >> lavirint[i][j];
            
            if(lavirint[i][j] == 'S') {
                si = i;
                sj = j;
            }
            if(lavirint[i][j] == 'E') {
                ei = i;
                ej = j;
            }
        }
    }
    int di[] = {+1, -1, 0, 0};
    int dj[] = {0,  0,  - 1, +1};
    
    memset(poseteno, 0, sizeof poseteno);
    queue Q;
    Q.push(si);
    Q.push(sj);
    Q.push(0);
    
    poseteno[si][sj] = 1;
    while(Q.size() > 0) {
        int ci = Q.front();
        Q.pop();
        int cj = Q.front();
        Q.pop();
        int cekor = Q.front();
        Q.pop();
        if(lavirint[ci][cj] == 'E') {
            cout << cekor << 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 < redovi and tj >= 0 and tj < koloni and poseteno[ti][tj] == 0) {
                if(lavirint[ti][tj] == '#') {
                    sashe[ti][tj] = cekor + 1;
                    poseteno[ti][tj] = 1;
                }
                else {
                    Q.push(ti);
                    Q.push(tj);
                    Q.push(cekor + 1);
                    poseteno[ti][tj] = 1;
                }
            }
        }
    }
    
    memset(poseteno, 0, sizeof poseteno);
    queue Q2;
    Q2.push(ei);
    Q2.push(ej);
    Q2.push(0);
    poseteno[ei][ej] = 1;
    while(Q2.size() > 0) {
        int ci = Q2.front();
        Q2.pop();
        int cj = Q2.front();
        Q2.pop();
        int cekor = Q2.front();
        Q2.pop();
        
        for(int k = 0; k < 4; k++) {
            int ti = ci + di[k];
            int tj = cj + dj[k];
            if(ti >= 0 and ti < redovi and tj >= 0 and tj < koloni and poseteno[ti][tj] == 0) {
                if(lavirint[ti][tj] == '#') {
                    elena[ti][tj] = cekor + 1;
                    poseteno[ti][tj] = 1;
                }
                else {
                    Q2.push(ti);
                    Q2.push(tj);
                    Q2.push(cekor + 1);
                    poseteno[ti][tj] = 1;
                }
            }
        }
    }
    int najgolem_pat = -1;
    for(int i = 0; i < redovi; i++) {
        for(int j = 0; j < koloni; j++) {
            if(lavirint[i][j] == '#') {
                if(elena[i][j] != -1 and sashe[i][j] != -1) {
                    if(najgolem_pat < elena[i][j] + sashe[i][j]) {
                        najgolem_pat = elena[i][j] + sashe[i][j];
                    }
                }
            }
            
        }
    }
    cout << najgolem_pat << endl;

    return 0;
}
/*
 
 S..#E
 ###..
 #....
 .....
 
 **/