using System;
using static System.Console;
using System.Linq;
using System.Collections.Generic;

class Program
{
    static int NN => int.Parse(ReadLine());
    static int[] NList => ReadLine().Split().Select(int.Parse).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 map = new int[h][];
        for (var i = 0; i < h; ++i) map[i] = Enumerable.Repeat(100, w).ToArray();
        map[si][sj] = 0;
        WriteLine(DFS(h, w, si, sj, gi, gj, map));
    }
    static int[] mx = new int[] { -1, 1, 0, 0 };
    static int[] my = new int[] { 0, 0, -1, 1 };
    static int DFS(int h, int w, int cx, int cy, int gi, int gj, int[][] map)
    {
        for (var i = 0; i < 4; ++i)
        {
            var nx = cx + mx[i];
            var ny = cy + my[i];
            if (nx < 0 || nx >= h || ny < 0 || ny >= w) continue;
            if (map[nx][ny] + 1 < map[cx][cy]) return 0;
        }
        if (cx == gi && cy == gj) return 1;
        var ans = 0;
        for (var i = 0; i < 4; ++i)
        {
            var nx = cx + mx[i];
            var ny = cy + my[i];
            if (nx < 0 || nx >= h || ny < 0 || ny >= w) continue;
            if (map[nx][ny] < map[cx][cy]) continue;
            map[nx][ny] = map[cx][cy] + 1;
            ans += DFS(h, w, nx, ny, gi, gj, map);
            map[nx][ny] = 100;
        }
        return ans;
    }
}