#include<bits/stdc++.h>
using namespace std;
typedef long long ll;

ll n,m,mp[109][109];
ll sx,sy,gx,gy;
ll dx[4]= {1,-1,0,0};
ll dy[4]= {0,0,1,-1};
bool vis[109][109];

struct _NODE
{
	ll x,y;
};
queue<_NODE> qe;

signed main()
{
	scanf("%lld %lld %lld %lld %lld %lld",&n,&m,&sx,&sy,&gx,&gy);
	memset(vis,false,sizeof(vis));
	for(int i=1; i<=n; i++)
		for(int j=1; j<=m; j++)
		{
			char ch;
			cin>>ch;
			mp[i][j]=ch-'0';
		}
	qe.push((_NODE)
	{
		sx,sy
	});
	vis[sx][sy]=true;
	while(!qe.empty())
	{
		_NODE nw=qe.front();
		qe.pop();
		ll nwx=nw.x,nwy=nw.y;
		if(nwx==gx&&nwy==gy)
		{
			printf("YES\n");
			return 0;
		}
		for(int k=0; k<4; k++)
		{
			_NODE to=(_NODE)
			{
				nwx+dx[k],nwy+dy[k]
			};
			if(to.x<1||to.x>n&&to.y<1||to.y>m||vis[to.x][to.y]||(abs(mp[to.x][to.y]-mp[nwx][nwy])!=1&&mp[to.x][to.y]!=mp[nwx][nwy])) ;
			else
			{
				qe.push(to);
				vis[to.x][to.y]=true;
			}
			to=(_NODE)
			{
				to.x+dx[k],to.y+dy[k]
			};
			if(to.x<1||to.x>n&&to.y<1||to.y>m||vis[to.x][to.y]||mp[to.x-dx[k]][to.y-dy[k]]>=mp[nwx][nwy]||mp[to.x][to.y]!=mp[nwx][nwy])
				continue;
			qe.push(to);
			vis[to.x][to.y]=true;
		}
	}
	printf("NO\n");
	return 0;
}