#include <bits/stdc++.h>
#define int long long
#define xx first
#define yy second
using namespace std;


const int N = 110;
typedef pair<int , int> PII;
queue<PII> q;    
int n, m, a, b, c, h;
int g[N][N]; 
int d[N][N]; 

int bfs() {
    memset(d, -1, sizeof(d));  
    d[a][b] = 0;
    int dx[4] = {-1, 0, 1, 0}, dy[4] = {0, 1, 0, -1}; 
    while (q.size()) {
        auto t = q.front();
        q.pop();

        for (int i = 0; i < 4; i++) {
            int x = t.xx + dx[i];
            int y = t.yy + dy[i];
            if (x >= 1 && x <= n && y >= 1 && y <= m && g[x][y] == 1 && d[x][y] == -1) {
                d[x][y] = d[t.xx][t.yy] + 1; 
                q.push({x, y}); 
                if (c == x && y == h) return d[x][y];
            }
        }
    }
    return -1;
}

void solve() {
    cin >> n >> m;
    for (int i = 1; i <= n; i++)
        for (int j = 1; j <= m; j++)
            cin >> g[i][j]; 

    cin >> a >> b >> c >> h;
        q.push(make_pair(a,b));
    cout << bfs() << endl;

}

signed main() {
    int t = 1;
    // cin >> t;
    while (t--) solve();
    return 0;
}