#include <bits/stdc++.h>
#define FOR(i,a,b) for (int i=(a);i<(b);i++)
#define FORR(i,a,b) for (int i=(a);i>=(b);i--)
#define pb push_back
#define pcnt __builtin_popcount
#define show(x) cout<<#x<<" = "<<x<<endl;
#define maxs(x,y) x = max(x,y)
#define mins(x,y) x = min(x,y)
#define fi first
#define se second
#define rng(a) a.begin(),a.end()
#define each(it,c) for(__typeof((c).begin()) it=(c).begin();it!=(c).end();it++)
#define sz(x) (int)(x).size()
#define mp make_pair

using namespace std;
typedef long long ll;
typedef pair<int,int> pii;
typedef vector<int> vi;
typedef vector<vi> vvi;
typedef vector<pii> vpii;
typedef set<int> si;
typedef pair<ll,ll> pll;
typedef vector<ll> vl;
typedef vector<vl> vvl;
typedef vector<pll> vpll;
typedef set<ll> sl;
template<typename T>string join(vector<T>&v)
{stringstream s;FOR(i,0,sz(v))s<<' '<<v[i];return s.str().substr(1);}
ll gcd(ll a,ll b){if(a>b)swap(a,b);for(;a>0;b%=a,swap(a,b));return b;}
int modpow(ll a,ll n,int m){if(a==0)return a;ll p=1;for(;n>0;n/=2,a=a*a%m)if(n&1)p=p*a%m;return(int)p;}
void dout(double d){printf("%.12f\n",d);}

const int iinf = 1e9;
const ll linf = 1e18;
const int mod = 1e9+7;
const double pi = acos(-1);
const double eps = 1e-10;

int h, w, m[50][50], s[2], g[2];
string st;
main(){
  cin.tie(0);
  ios::sync_with_stdio(false);
  cin >> h >> w;
  cin >> s[0] >> s[1] >> g[0] >> g[1];
  s[0]--;s[1]--;g[0]--;g[1]--;
  FOR(i, 0, h){
    cin >> st;
    FOR(j, 0, w) m[i][j] = st[j] - '0';
  }
  vector<pair<pii, int> > D;
  FOR(i, -1, 2){
    D.pb(mp(mp(1, 0), i));
    D.pb(mp(mp(-1,0), i));
    D.pb(mp(mp(0, 1), i));
    D.pb(mp(mp(0,-1), i));
  }
  D.pb(mp(mp(2, 0), 0));
  D.pb(mp(mp(-2,0), 0));
  D.pb(mp(mp(0, 2), 0));
  D.pb(mp(mp(0,-2), 0));
  queue<pii> q;
  pii ss = mp(s[0], s[1]), gg = mp(g[0], g[1]);
  q.push(ss);
  set<pii> yy;
  yy.insert(ss);
  while(!q.empty()){
    pii t = q.front();
    q.pop();
    if(t == gg){
      cout << "YES" << endl;
      return 0;
    }
    each(itr, D){
      int x, y;
      x = t.fi + itr->fi.fi;
      y = t.se + itr->fi.se;
      if(0 <= x && x < h && 0 <= y && y < w && m[x][y] == m[t.fi][t.se] + itr->se){
        if(abs(itr->fi.fi) + abs(itr->fi.se) == 2 && m[(x+t.fi)/2][(y+t.se)/2] > m[x][y])continue;
        pii tt = mp(x, y);
        if(yy.find(tt) == yy.end()){
          yy.insert(tt);
          q.push(tt);
        }
      }
    }
  }
  cout << "NO" << endl;
  return 0;
}