#include <cstdio>
#include <algorithm>
#include <queue>
#include <cstring>

using namespace std;

const int INF = 0x3f3f3f3f;
const int nmax = 505;

int n, m;
int dx[] = {-1, -1, -1, 0, 1, 1, 1, 0};
int dy[] = {-1, 0, 1, 1, 1, 0, -1, -1};
int a[nmax][nmax];
int D[nmax][nmax][8];
bool iq[nmax][nmax][8];

inline int cost(int pd, int nd) {
    if (nd < pd)
        swap(nd, pd);

    if (nd - pd < pd - nd + 8)
        return nd - pd;

    return pd - nd + 8;
}

bool valid(int x, int y) {
    return (x >= 1 && x <= n) && (y >= 1 && y <= m) && a[x][y] == 0;
}

int main() {
    int x1, y1, x2, y2;

    freopen("car.in", "r", stdin);
    freopen("car.out", "w", stdout);

    scanf("%d %d", &n, &m);
    scanf("%d %d %d %d", &x1, &y1, &x2, &y2);
    for (int i = 1; i <= n; i++) {
        for (int j = 1; j <= m; j++) {
            scanf("%d", &a[i][j]);
        }
    }

    memset(D, INF, sizeof(D));

    queue<pair<pair<int, int>, int> > q;
    for (int k = 0; k < 8; k++) {
        D[x1][y1][k] = 0;
        int x = x1 + dx[k];
        int y = y1 + dy[k];

        if (valid(x, y)) {
            q.push(make_pair(make_pair(x, y), k));
            iq[x][y][k] = true;
            D[x][y][k] = 0;
        }
    }

    while (!q.empty()) {
        int x = q.front().first.first;
        int y = q.front().first.second;
        int pd = q.front().second;
        iq[x][y][pd] = false;
        q.pop();

        for (int k = 0; k < 8; k++) {
            int nx = x + dx[k];
            int ny = y + dy[k];
            int cst = cost(pd, k);
            if (valid(nx, ny)) {
                if (D[nx][ny][k] > D[x][y][pd] + cst) {
                    D[nx][ny][k] = D[x][y][pd] + cst;
                    if (!iq[nx][ny][k]) {
                        iq[nx][ny][k] = true;
                        q.push(make_pair(make_pair(nx, ny), k));
                    }
                }
            }
        }
    }

    int ans = INF;
    for (int k = 0; k < 8; k++) {
        ans = min(ans, D[x2][y2][k]);
    }

    if (ans == INF)
        printf("-1\n");
    else
        printf("%d\n", ans);

    return 0;
}