#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;
    for(int i = 0; i < redovi; i++) {
        for(int j = 0; j < koloni; j++) {
            cin >> lavirint[i][j];
            if(lavirint[i][j] == 'P') {
                si = i;
                sj = j;
            }
            poseteno[i][j] = 0;
        }
    }
    int direction_i[] = {+1, -1, 0, 0};
    int direction_j[] = {0,  0, +1,-1};
    queue<int> Q;
    Q.push(si);
    Q.push(sj);
    Q.push(0);

    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] == 'K') {
            cout << cekor << endl;
            break;
        }
        for(int i = 0; i < 4; i++) {
            int ti = ci + direction_i[i];
            int tj = cj + direction_j[i];
            if(ti < redovi and ti >= 0 and tj < koloni and tj >= 0 and lavirint[ti][tj] != '#' and poseteno[ti][tj] == 0) {
                Q.push(ti);
                Q.push(tj);
                Q.push(cekor + 1);
                poseteno[ti][tj] = 1;
            }
        }
    }
    return 0;
}
/*
 8 8
  P...#..A
  ........
  ...#K...
  B.......
  ##......
  ########
  ........
  ........


 **/