#include <iostream>
#include <vector>
#include <deque>

using namespace std;

struct point {
    int i, j;
    int way;

    explicit point(int a = 0, int b = 0, int w = 0) : i(a), j(b), way(w) {
    }
};

int main() {
    int h, w;
    cin >> h >> w;
    vector<vector<vector<int>>> field(8, vector<vector<int>>(h));
    for (int k = 0; k < 8; ++k) {
        for (int i = 0; i < h; ++i) {
            field[k][i].resize(w);
            for (int j = 0; j < w; ++j) {
                char t;
                cin >> t;
                if (t == '.') {
                    field[k][i][j] = 1000000;
                }
                if (t == 'X') {
                    field[k][i][j] = -1;
                }
            }
        }
    }
    int sx, sy;
    cin >> sx >> sy;
    int tx, ty;
    cin >> tx >> ty;
    int way = 0;
    deque<point> que;
    --sx;
    sy = h - sy;
    --tx;
    ty = h - ty;
    for (int i = 0; i < 8; ++i) {
        field[i][sy][sx] = 0;
    }
    que.push_back(point(sy, sx, 0));
    vector<int> di = {-1, 0, 1, 0, -1, 1, 1, -1};
    vector<int> dj = {0, 1, 0, -1, 1, 1, -1, -1};
    while (!que.empty()) {
        point cur(que.front().i, que.front().j, que.front().way);
        que.pop_front();
        for (int k = 1; k <= 8; ++k) {
            point neib(cur.i + di[k - 1], cur.j + dj[k - 1]);
            if (neib.i < 0 || neib.i >= h || neib.j < 0 || neib.j >= w) {
                continue;
            }
            if (field[k - 1][neib.i][neib.j] == -1) {
                continue;
            }
            if (cur.way == k) {
                if (field[k - 1][neib.i][neib.j] > field[k - 1][cur.i][cur.j]) {
                    field[k - 1][neib.i][neib.j] = field[k - 1][cur.i][cur.j];
                    que.push_front(point(neib.i, neib.j, k));
                }
            } else {
                if (field[k - 1][neib.i][neib.j] > field[k - 1][cur.i][cur.j] + 1) {
                    field[k - 1][neib.i][neib.j] = field[k - 1][cur.i][cur.j] + 1;
                    que.push_back(point(neib.i, neib.j, k));
                }
            }
        }
    }
    int ans = field[0][ty][tx];
    for (int i = 1; i < 8; ++i) {
        ans = min(ans, field[i][ty][tx]);
    }
    if (ans == -1 || ans == 1000000000) {
        cout << -1 << endl;
        return 0;
    }
    cout << ans << endl;
    return 0;
}