#include <fstream>
#include <queue>

#define MAX 512
#define DMAX 8
#define INF 32000

using namespace std;

short dp[DMAX][MAX][MAX], dX[] = {-1, -1, 0, 1, 1, 1, 0, -1}, dY[] = {0, 1, 1, 1, 0, -1, -1, -1}, n, m;
bool a[MAX][MAX];

struct punct
{
    int x, y, d;
}start, stop, pct;

queue<punct> q[2];

void init()
{
    for(int i = 0; i <= n + 1; i++)
        a[i][0] = a[i][m + 1] = true;
    for(int i = 0; i <= m + 1; i++)
        a[0][i] = a[n + 1][i] = true;
    for(int i = 0; i < DMAX; i++)
    {
        start.d = i;
        dp[start.x][start.y][start.d] = 0;
        q[0].push(start);
    }
}

int main()
{
    ifstream in("car.in");
    in>>n>>m>>start.x>>start.y>>stop.x>>stop.y;
    for(int i = 1; i <= n; i++)
        for(int j = 1; j <= m; j++)
        {
            in>>a[i][j];
            for(int k = 0; k < DMAX; k++)
                dp[i][j][k] = INF;
        }
    in.close(); init();
    int p = 1; ofstream out("car.out");
    while(q[0].size() + q[1].size() != 0)
    {
        p = 1 - p;
        while(!q[p].empty())
        {
            pct = q[p].front(); q[p].pop();
            int x = pct.x, y = pct.y, dir = pct.d;

            if(x == stop.x && y == stop.y)
            {
                out<<dp[x][y][dir];
                out.close();
                return 0;
            }

            pct.d = ((dir + 1) >= 8 ? dir - 7 : dir + 1);
            if(dp[pct.x][pct.y][pct.d] > dp[x][y][dir] + 1)
            {
                dp[pct.x][pct.y][pct.d] = dp[x][y][dir] + 1;
                q[1 - p].push(pct);
            }

            pct.d = ((dir + 7) >= 8 ? dir - 1 : dir + 7);
            if(dp[pct.x][pct.y][pct.d] > dp[x][y][dir] + 1)
            {
                dp[pct.x][pct.y][pct.d] = dp[x][y][dir] + 1;
                q[1 - p].push(pct);
            }

            pct.x = x + dX[dir];
            pct.y = y + dY[dir];
            pct.d = dir;
            if(!a[pct.x][pct.y] && dp[pct.x][pct.y][pct.d] > dp[x][y][dir])
            {
                dp[pct.x][pct.y][pct.d] = dp[x][y][dir];
                q[p].push(pct);
            }
        }
    }
    out<<"-1";
    out.close();
    return 0;
}