using System;
using System.Text;
using System.Linq;
using System.Collections.Generic;

public class Program
{
    public void Proc() {
        Reader.IsDebug = false;
        int[] inpt = Reader.ReadLine().Split(' ').Select(a=>int.Parse(a)).ToArray();

        int h = inpt[0];
        int w = inpt[1];

        inpt = Reader.ReadLine().Split(' ').Select(a=>int.Parse(a)).ToArray();
        
        int sY = inpt[0] - 1;
        int sX = inpt[1] - 1;

        int gY = inpt[2] - 1;
        int gX = inpt[3] - 1;

        int[,] map = new int[h, w];
        bool[,] flags = new bool[h, w];

        for(int i=0; i<h; i++) {
            string tmp = Reader.ReadLine();
            for(int j=0; j<w; j++) {
                map[i,j] = int.Parse(tmp[j].ToString());
            }        
        }

        flags[sY, sX] = true;
        Queue<int[]> que = new Queue<int[]>();
        que.Enqueue(new int[]{sY, sX});
        while(que.Count > 0) {
            int[] pos = que.Dequeue();
            if(pos[0] == gY && pos[1] == gX) {
                continue;
            }

            List<int[]> next = new List<int[]>();
            for(int i=pos[0]-1; i<=pos[0]+1; i++) {
                for(int j=pos[1]-1; j<=pos[1]+1; j++) {
                    if(i==pos[0] && j==pos[1]) {
                        continue;
                    }
                    if(i!=pos[0] && j!=pos[1]) {
                        continue;
                    }
                    if(i<0||i>=h||j<0||j>=w) {
                        continue;
                    }
                    if(Math.Abs(map[i,j] - map[pos[0], pos[1]]) <= 1) {
                        next.Add(new int[]{i,j});
                    }
                }
            }
            for(int i=pos[0]-2; i<=pos[0]+2; i+=2) {
                for(int j=pos[1]-2; j<=pos[1]+2; j+=2) {
                    if(i==pos[0] && j==pos[1]) {
                        continue;
                    }
                    if(i!=pos[0] && j!=pos[1]) {
                        continue;
                    }
                    if(i<0||i>=h||j<0||j>=w) {
                        continue;
                    }
                    if(map[i,j] == map[pos[0], pos[1]]) {
                        int tani = 0;
                        if(i == pos[0]) {
                            tani = map[i, (pos[1] + j)/2];
                        } else {
                            tani = map[(i+pos[0])/2, j];
                        }
                        if(tani < map[i,j]) {
                            next.Add(new int[]{i,j});
                        }
                    }
                }
            }
            foreach(int[] nextPos in next) {
                if(flags[nextPos[0], nextPos[1]]) {
                    continue;
                }
                flags[nextPos[0], nextPos[1]] = true;
                que.Enqueue(nextPos);
            }
        }

        Console.WriteLine(flags[gY, gX]?"YES":"NO");        
    }


    public class Reader {
        public static bool IsDebug = true;
        private static System.IO.StringReader SReader;
        private static string InitText = @"



10 12
4 1 1 12
879572576859
445569966665
033345689389
011246557476
000224557745
000022346548
000000425665
000002223544
000000003223
000000000243



";
        public static string ReadLine() {
            if(IsDebug) {
                if(SReader == null) {
                    SReader = new System.IO.StringReader(InitText.Trim());
                }
                return SReader.ReadLine();
            } else {
                return Console.ReadLine();
            }
        }
    }
    public static void Main(string[] args)
    {
        Program prg = new Program();
        prg.Proc();
    }
}