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

struct fact
{
    int lin, col, d;
};
int v[505][505], dist[505][505];
queue<fact>q;
int dirl[]={-1, -1, -1, 0, 1, 1, 1, 0};
int dirc[]={-1, 0, 1, 1, 1, 0, -1, -1};
signed main()
{
    ifstream cin("car.in");
    ofstream cout("car.out");
    
    int n, m, ls, cs, lf, cf, l, c, x, y, d, d2, nr;
    cin>>n>>m>>ls>>cs>>lf>>cf;
    for(int i=1; i<=n; i++)
    {
        for(int j=1; j<=m; j++)
        {
            cin>>v[i][j];
            dist[i][j]=INT_MAX;
        }
    }
    if(v[ls][cs]==1)
    {
        cout<<"-1";
        return 0;
    }
    dist[ls][cs]=0;
    q.push({ls, cs, -1});
    while(!q.empty())
    {
        fact crn=q.front();
        l=crn.lin;c=crn.col;d=crn.d;
        q.pop();
        for(int i=0; i<=7; i++)
        {
            x=l+dirl[i];y=c+dirc[i];
            d2=i;
            if(x<1 || y<1 || x>n || y>m)
            continue;
            if(d==-1)
            nr=0;
            else
            {
                nr=abs(d-d2);
                if(nr>4)
                nr=8-nr;
            }
            //cout<<l<<" "<<c<<" "<<x<<" "<<y<<endl;
            //cout<<d<<" "<<d2<<" "<<nr<<endl;
            if(v[x][y]==0 && dist[x][y]>dist[l][c]+nr)
            {
                dist[x][y]=dist[l][c]+nr;
                q.push({x, y, d2});
            }
        }
    }
    if(dist[lf][cf]==INT_MAX)
    cout<<"-1";
    else
    cout<<dist[lf][cf];

    return 0;
}