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

namespace No424{
    public class Program{
        public static void Main(string[] args){
            var sr = new StreamReader();
            //---------------------------------
            var H = sr.Next<int>();
            var W = sr.Next<int>();
            var Sy = sr.Next<int>() - 1;
            var Sx = sr.Next<int>() - 1;
            var Gy = sr.Next<int>() - 1;
            var Gx = sr.Next<int>() - 1;
            var B = sr.Next<string>(H).Select(s => s.Select(c => c - '0').ToArray()).ToArray();

            var dx = new[]{0, 1, 0, -1};
            var dy = new[]{1, 0, -1, 0};
            Func<int, int, bool> isInside = (x, y) => 0 <= x && x < W && 0 <= y && y < H;
            var visit = new bool[H, W].ToJaggedArray();
            var que = new Queue<int>();
            que.Enqueue(Sx);
            que.Enqueue(Sy);

            while(que.Count > 0){
                var x = que.Dequeue();
                var y = que.Dequeue();
                for(var i = 0; i < 4; i++){
                    var nx = x + dx[i];
                    var ny = y + dy[i];
                    var nnx = x + dx[i] * 2;
                    var nny = y + dy[i] * 2;
                    if(isInside(nx, ny) && !visit[ny][nx] && Math.Abs(B[y][x] - B[ny][nx]) <= 1){
                        visit[ny][nx] = true;
                        que.Enqueue(nx);
                        que.Enqueue(ny);
                    }
                    if(isInside(nnx, nny) && !visit[nny][nnx] && B[y][x] == B[nny][nnx] && B[y][x] > B[ny][nx]){
                        visit[nny][nnx] = true;
                        que.Enqueue(nnx);
                        que.Enqueue(nny);
                    }
                }
            }

            Console.WriteLine(visit[Gy][Gx] ? "YES" : "NO");
            //---------------------------------
        }
    }

    public static class ExMethod{
        public static T[][] ToJaggedArray<T>(this T[,] src){
            var x = src.GetLength(1);
            var y = src.GetLength(0);
            var ret = new T[y][];

            for(var i = 0; i < y; i++){
                ret[i] = new T[x];
                for(var j = 0; j < x; j++){
                    ret[i][j] = src[i, j];
                }
            }

            return ret;
        } 
    }

    public class StreamReader{
        private readonly char[] _c = {' '};
        private int _index = -1;
        private string[] _input = new string[0];
        private readonly System.IO.StreamReader _sr = new System.IO.StreamReader(Console.OpenStandardInput());

        public T Next<T>(){
            if(_index == _input.Length - 1){
                _index = -1;
                while(true){
                    string rl = _sr.ReadLine();
                    if(rl == null){
                        if(typeof(T).IsClass) return default(T);
                        return (T)typeof(T).GetField("MinValue").GetValue(null);
                    }
                    if(rl != ""){
                        _input = rl.Split(_c, StringSplitOptions.RemoveEmptyEntries);
                        break;
                    }
                }
            }
            return (T)Convert.ChangeType(_input[++_index], typeof(T), System.Globalization.CultureInfo.InvariantCulture);
        }

        public T[] Next<T>(int x){
            var ret = new T[x];
            for(var i = 0; i < x; ++i) ret[i] = Next<T>();
            return ret;
        }

        public T[][] Next<T>(int y, int x){
            var ret = new T[y][];
            for(var i = 0; i < y; ++i) ret[i] = Next<T>(x);
            return ret;
        }
    }
}