#include<iostream>
#include<cstdio>
#include<cstdlib>
#include<algorithm>
#include<vector>
#include<string>
#include<sstream>
#include<iomanip>
#include<utility>
#include<cmath>
#include<set>
#include<list>
#include<queue>
#include<stack>
#include<map>
#include<cstring>
using namespace std;
typedef long long int ll;
class disjointset
{
public:
	vector<int> rank;
	vector<int> p;
	
	void makeset(int x)
	{
		p[x]=x;
		rank[x]=0;
		return;
	}
	disjointset(int s)
	{
		rank.resize(s);
		p.resize(s);
		for(int i=0;i<s;i++)makeset(i);
		return;
	}
	int findset(int x)
	{
		if(x!=p[x])p[x]=findset(p[x]);
		return p[x];
	}
	void link(int x,int y)
	{
		if(rank[x]>rank[y])p[y]=x;
		else
		{
			p[x]=y;
			if(rank[x]==rank[y])rank[y]++;
		}
		return;
	}
	bool same(int x,int y)
	{
		return findset(x)==findset(y);
	}
	void unite(int x,int y)
	{
		link(findset(x),findset(y));
		return;
	}
};
string s[50];
int h,w,sx,sy,gx,gy;
disjointset d=disjointset(50*50);
int dx[8]={1,-1,0,0,2,-2,0,0};
int dy[8]={0,0,1,-1,0,0,2,-2};
bool used[50][50]={};
int toi(char a)
{
	stringstream ss;
	ss<<a;
	int ans;
	ss>>ans;
	return ans;
}
void dfs(int x,int y)
{
	used[x][y]=true;
	for(int r=0;r<8;r++)
	{
		int tx=x+dx[r];
		int ty=y+dy[r];
		if(used[tx][ty])continue;
		if(tx<0||ty<0||tx>=h||ty>=w)continue;
		if(r<4)
		{
			if(abs(toi(s[tx][ty])-toi(s[x][y]))<=1)
			{
				d.unite(x*w+y,tx*w+ty);
				dfs(tx,ty);
			}
		}
		else
		{
			if(toi(s[tx][ty])==toi(s[x][y]))
			{
				int a=toi(s[(tx+x)/2][(ty+y)/2]);
				if(a<=toi(s[x][y]))
				{
					d.unite(x*w+y,tx*w+ty);
					dfs(tx,ty);
				}
			}
		}
	}
	return;
}
int main()
{
	cin>>h>>w>>sx>>sy>>gx>>gy;
	sx--;sy--;gx--;gy--;
	for(int i=0;i<h;i++)cin>>s[i];
	dfs(sx,sy);
	if(d.same(sx*w+sy,gx*w+gy))cout<<"YES"<<endl;
	else cout<<"NO"<<endl;
	return 0;
}