#include<iostream>
#include<vector>
#include<string>
#include<cmath>
#include<queue>

using namespace std;

typedef pair<int,int> P;

int h,w;
int sx,sy,gx,gy;
vector<vector<int>> b(55,vector<int>(55,-1));
vector<vector<bool>> used(55,vector<bool>(55,false));
const int dx[] = {1,0,-1,0};
const int dy[] = {0,1,0,-1};
const int dx2[] = {2,0,-2,0};
const int dy2[] = {0,2,0,-2};

bool bfs(){
  queue<P> que;
  que.push(P(sx,sy));
  used[sx][sy] = true;
  while(!que.empty()){

    P cur = que.front();que.pop();
    if(cur.first == gx && cur.second == gy){
      return true;
    }

    for(int i=0;i < 4;i++){
      int nx = cur.first + dx[i],ny = cur.second + dy[i];
      int nx2 = cur.first + dx2[i],ny2 = cur.second + dy2[i];

      if(nx > 0 && nx <= h && ny > 0 && ny <= w){
        int height = b[nx][ny] - b[cur.first][cur.second];
        int height2 = b[nx2][ny2] - b[cur.first][cur.second];
        if(height == 0 || height == 1 || height == -1){
          if(!used[nx][ny]) que.push(P(nx,ny));
          used[nx][ny] = true;
        }else if(height <= -1 && height2 == 0){
          if(!used[nx2][ny2]) que.push(P(nx2,ny2));
          used[nx2][ny2] = true;
        }
      }
    }

  }
  return false;
}

int main(){
  cin >> h >> w;
  cin >> sx >> sy >> gx >> gy;
  for(int i=1;i <= h;i++){
    string s;
    cin >> s;
    for(int j=1;j <= w;j++){
      b[i][j] = s[j-1] - '0';
    }
  }
  if(bfs()) cout << "YES" << endl;
  else cout << "NO" << endl;
  return 0;
}