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

int main()
{
    int redovi, koloni;
    cin >> redovi >> koloni;
    
    char lavirint[redovi][koloni];
    int poseteno[redovi][koloni];
    int si, sj;
    int ai, aj;
    int bi, bj;
    int pi, pj;
    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] == 'A') {
                ai = i;
                aj = j;
            }
            if(lavirint[i][j] == 'B') {
                bi = i;
                bj = j;
            }
            if(lavirint[i][j] == 'P') {
                pi = i;
                pj = j;
            }
            poseteno[i][j] = 0;
        }
    }
    queue<int> Q;
    Q.push(si);
    Q.push(sj);
    Q.push(0);
    int pat1 = 0;
    while(Q.size() > 0) {
        int ci = Q.front();
        Q.pop();
        int cj = Q.front();
        Q.pop();
        int cekori = Q.front();
        Q.pop();
        if(lavirint[ci][cj] == 'A') {
            pat1 += cekori;
            break;
        }
        if(ci + 1 < redovi and lavirint[ci + 1][cj] != '#' and poseteno[ci + 1][cj] == 0) {
            Q.push(ci + 1);
            Q.push(cj);
            Q.push(cekori + 1);
            poseteno[ci + 1][cj] = 1;
        }
        if(ci - 1 >= 0 and lavirint[ci - 1][cj] != '#' and poseteno[ci - 1][cj] == 0) {
            Q.push(ci - 1);
            Q.push(cj);
            Q.push(cekori + 1);
            poseteno[ci - 1][cj] = 1;
        }
        if(cj + 1 < koloni and lavirint[ci][cj + 1] != '#' and poseteno[ci][cj + 1] == 0) {
            Q.push(ci);
            Q.push(cj + 1);
            Q.push(cekori + 1);
            poseteno[ci][cj + 1] = 1;
        }
        if(cj - 1 >= 0 and lavirint[ci][cj - 1] != '#' and poseteno[ci][cj - 1] == 0) {
            Q.push(ci);
            Q.push(cj - 1);
            Q.push(cekori + 1);
            poseteno[ci][cj - 1] = 1;
        }
    }
    for(int i = 0; i < redovi; i++) {
        for(int j = 0; j < koloni; j++) {
            poseteno[i][j] = 0;
        }
    }
    queue<int> Q1;
    Q1.push(ai);
    Q1.push(aj);
    Q1.push(0);
    poseteno[ai][aj] = 1;
    
    while(Q1.size() > 0) {
        int ci = Q1.front();
        Q1.pop();
        int cj = Q1.front();
        Q1.pop();
        int cekori = Q1.front();
        Q1.pop();
        
        if(lavirint[ci][cj] == 'P') {
            pat1 += cekori;
            break;
        }
        if(ci + 1 < redovi and lavirint[ci + 1][cj] != '#' and poseteno[ci + 1][cj] == 0) {
            Q1.push(ci + 1);
            Q1.push(cj);
            Q1.push(cekori + 1);
            poseteno[ci + 1][cj] = 1;
        }
        if(ci - 1 >= 0 and lavirint[ci - 1][cj] != '#' and poseteno[ci - 1][cj] == 0) {
            Q1.push(ci - 1);
            Q1.push(cj);
            Q1.push(cekori + 1);
            poseteno[ci - 1][cj] = 1;
        }
        if(cj + 1 < koloni and lavirint[ci][cj + 1] != '#' and poseteno[ci][cj + 1] == 0) {
            Q1.push(ci);
            Q1.push(cj + 1);
            Q1.push(cekori + 1);
            poseteno[ci][cj + 1] = 1;
        }
        if(cj - 1 >= 0 and lavirint[ci][cj - 1] != '#' and poseteno[ci][cj - 1] == 0) {
            Q1.push(ci);
            Q1.push(cj - 1);
            Q1.push(cekori + 1);
            poseteno[ci][cj - 1] = 1;
        }
    }
    
    for(int i = 0; i < redovi; i++) {
        for(int j = 0; j < koloni; j++) {
            poseteno[i][j] = 0;
        }
    }
    
    queue<int> Q2;
    Q2.push(si);
    Q2.push(sj);
    Q2.push(0);
    poseteno[si][sj] = 1;
    int pat2 = 0;
    while(Q2.size() > 0) {
        int ci = Q2.front();
        Q2.pop();
        int cj = Q2.front();
        Q2.pop();
        int cekori = Q2.front();
        Q2.pop();
        
        if(lavirint[ci][cj] == 'B') {
            pat2 += cekori;
            break;
        }
        if(ci + 1 < redovi and lavirint[ci + 1][cj] != '#' and poseteno[ci + 1][cj] == 0) {
            Q2.push(ci + 1);
            Q2.push(cj);
            Q2.push(cekori + 1);
            poseteno[ci + 1][cj] = 1;
        }
        if(ci - 1 >= 0 and lavirint[ci - 1][cj] != '#' and poseteno[ci - 1][cj] == 0) {
            Q2.push(ci - 1);
            Q2.push(cj);
            Q2.push(cekori + 1);
            poseteno[ci - 1][cj] = 1;
        }
        if(cj + 1 < koloni and lavirint[ci][cj + 1] != '#' and poseteno[ci][cj + 1] == 0) {
            Q2.push(ci);
            Q2.push(cj + 1);
            Q2.push(cekori + 1);
            poseteno[ci][cj + 1] = 1;
        }
        if(cj - 1 >= 0 and lavirint[ci][cj - 1] != '#' and poseteno[ci][cj - 1] == 0) {
            Q2.push(ci);
            Q2.push(cj - 1);
            Q2.push(cekori + 1);
            poseteno[ci][cj - 1] = 1;
        }
        
    }
    
    for(int i = 0; i < redovi; i++) {
        for(int j = 0; j < koloni; j++) {
            poseteno[i][j] = 0;
        }
    }
    queue<int> Q3;
    Q3.push(bi);
    Q3.push(bj);
    Q3.push(0);
    poseteno[bi][bj] = 1;
    
    while(Q3.size() > 0) {
        int ci = Q3.front();
        Q3.pop();
        int cj = Q3.front();
        Q3.pop();
        int cekori = Q3.front();
        Q3.pop();
        
        if(lavirint[ci][cj] == 'P') {
            pat2 += cekori;
            break;
        }
        if(ci + 1 < redovi and lavirint[ci + 1][cj] != '#' and poseteno[ci + 1][cj] == 0) {
            Q3.push(ci + 1);
            Q3.push(cj);
            Q3.push(cekori + 1);
            poseteno[ci + 1][cj] = 1;
        }
        if(ci - 1 >= 0 and lavirint[ci - 1][cj] != '#' and poseteno[ci - 1][cj] == 0) {
            Q3.push(ci - 1);
            Q3.push(cj);
            Q3.push(cekori + 1);
            poseteno[ci - 1][cj] = 1;
        }
        if(cj + 1 < koloni and lavirint[ci][cj + 1] != '#' and poseteno[ci][cj + 1] == 0) {
            Q3.push(ci);
            Q3.push(cj + 1);
            Q3.push(cekori + 1);
            poseteno[ci][cj + 1] = 1;
        }
        if(cj - 1 >= 0 and lavirint[ci][cj - 1] != '#' and poseteno[ci][cj - 1] == 0) {
            Q3.push(ci);
            Q3.push(cj - 1);
            Q3.push(cekori + 1);
            poseteno[ci][cj - 1] = 1;
        }
    }
    if(pat1 < pat2) {
        cout << pat1 << endl;
    }
    else {
        cout << pat2 << endl;
    }
    
    return 0;
}

/*
 
 8 8
  S...#..A
  ........
  ...#P...
  B.......
  ##......
  ########
  ........
  ........

 
 **/