#include<iostream>
#include<queue>

using namespace std;
typedef pair<int, int> pii;

int main(){

   int h, w, sx, sy, gx ,gy;
   cin>> h>> w>> sx>> sy>> gx>> gy;
   sx--; sy--; gx--; gy--;
   string b[h];
   for(int i=0; i<h; i++){
      cin>> b[i];
   }
   int fld[h][w];
   for(int i=0; i<h; i++){
      for(int j=0; j<w; j++){
         fld[i][j]=b[i][j]-'0';
      }
   }

   pii dd[]={{1, 0}, {-1, 0}, {0, 1}, {0, -1}};
   int visited[h][w];
   int H, nh, ni, nj, nni, nnj;
   pii now;
   fill((int*)visited, (int*)visited+h*w, 0);
   queue<pii> Q;
   Q.push(pii(sx, sy));
   while(!Q.empty()){
      now=Q.front(); Q.pop();
      if(now.first==gx&&now.second==gy){
         cout<< "YES"<< endl;
         return 0;
      }
      visited[now.first][now.second]=1;
      for(pii d: dd){
         ni=now.first+d.first;
         nj=now.second+d.second;
         if(!(0<=ni&&ni<h&&0<=nj&&nj<w)) continue;
         H=fld[now.first][now.second];
         nh=fld[ni][nj];
         if(H<nh){
            if(H+1==nh){
               if(visited[ni][nj]) continue;
               Q.push(pii(ni, nj));
            }
         }else if(H==nh){
            if(visited[ni][nj]) continue;
            Q.push(pii(ni, nj));
         }else{
            if(H-1==nh){
               if(visited[ni][nj]) continue;
               Q.push(pii(ni, nj));
            }else{
               nni=ni+d.first;
               nnj=nj+d.second;
               if(!(0<=nni&&nni<h&&0<=nnj&&nnj<w)) continue;
               if(H==fld[nni][nnj]){
                  if(visited[nni][nnj]) continue;
                  Q.push(pii(nni, nnj));
               }
            }
         }
      }
   }
   cout<< "NO"<< endl;
   return 0;
}