using System;
using static System.Console;
using System.Linq;
using System.Collections.Generic;
using System.Globalization;
using System.Runtime.CompilerServices;
using System.Runtime.Intrinsics.X86;

class Program
{
    static int NN => int.Parse(ReadLine());
    static int[] NList => ReadLine().Split().Select(int.Parse).ToArray();
    static string[] SList(long n) => Enumerable.Repeat(0, (int)n).Select(_ => ReadLine()).ToArray();
    public static void Main()
    {
        Solve();
    }
    static void Solve()
    {
        var c = NList;
        var (h, w) = (c[0], c[1]);
        c = NList;
        var (si, sj) = (c[0] - 1, c[1] - 1);
        c = NList;
        var (gi, gj) = (c[0] - 1, c[1] - 1);
        var s = SList(h);
        var mx = new int[] { -1 , 1, 0, 0 };
        var my = new int[] { 0, 0, -1, 1 };
        var INF = int.MaxValue / 2;
        var len = new int[h][];
        for (var i = 0; i < h; ++i) len[i] = Enumerable.Repeat(INF, w).ToArray();
        len[si][sj] = 0;
        var q = new Queue<(int i, int j)>();
        q.Enqueue((si, sj));
        while (q.Count > 0)
        {
            var cur = q.Dequeue();
            if (cur.i == gi && cur.j == gj)
            {
                WriteLine(len[gi][gj]);
                return;
            }
            for (var p = 0; p < 4; ++p)
            {
                var ni = cur.i + mx[p];
                var nj = cur.j + my[p];
                if (ni < 0 || ni >= h || nj < 0 || nj >= w) continue;
                if (len[ni][nj] <= len[cur.i][cur.j] + 1) continue;
                len[ni][nj] = len[cur.i][cur.j] + 1;
                q.Enqueue((ni, nj));
            }
        }
    }
}