#define _CRT_SECURE_NO_WARNINGS
#include <stdio.h>
#include <algorithm>
#include <utility>
#include <functional>
#include <cstring>
#include <queue>
#include <stack>
#include <math.h>
#include <iterator>
#include <vector>
#include <string>
#include <set>
#include <math.h>
#include <iostream> 
#include<map>
#include <iomanip>
#include <stdlib.h>
#include <list>
#include <typeinfo>
#include <list>
#include <set>
using namespace std;
#define MAX_MOD 1000000007
#define REP(i,n) for(int i = 0;i < n;++i)
#define LONGINF 1000000000000000000
int can_arrive[100][100] = {};
int blocks[100][100] = {};
int plmi(int a, int b) {
	if (a == b) {
		return 1;
	}
	if (a == b - 1) {
		return 1;
	}
	if (a == b + 1) {
		return 1;
	}
	return 0;//±1
}
int main() {
	int h, w;
	cin >> h >> w;
	queue<pair<int, int>> start;
	int goalx, goaly;
	REP(i, 1) {
		int a, b, c, d;
		cin >> a >> b >> goalx >> goaly;
		pair<int, int> hoge = make_pair(a, b);
		start.push(hoge);
	}
	can_arrive[start.front().first][start.front().second] = 1;
	for (int i = 1;i <= h;++i) {
		string s;
		cin >> s;
		for (int q = 1; q <= w;++q) {
			blocks[i][q] = (int)s[q - 1] - (int)'0';
		}
	}
	while (start.empty() == false) {
		int x = start.front().first;
		int y = start.front().second;
		start.pop();
		if (x != 1) {
			if (plmi(blocks[x][y], blocks[x - 1][y]) == true) {
				if (can_arrive[x - 1][y] == false) {
					can_arrive[x - 1][y] = true;
					start.push(make_pair(x - 1, y));
				}
			}
			if (x != 2) {
				if (blocks[x][y] == blocks[x - 2][y]&&blocks[x][y] > blocks[x-1][y]) {
					if (can_arrive[x - 2][y] == false) {
						can_arrive[x - 2][y] = true;
						start.push(make_pair(x - 2, y));
					}
				}
			}
		}
		if (x != h) {
			if (plmi(blocks[x][y], blocks[x + 1][y]) == true) {
				if (can_arrive[x + 1][y] == false) {
					can_arrive[x + 1][y] = true;
					start.push(make_pair(x + 1, y));
				}
			}
			if (x + 1 != h) {
				if (blocks[x][y] == blocks[x+2][y]&&blocks[x][y] > blocks[x+1][y]) {
					if (can_arrive[x+2][y] == false) {
						can_arrive[x+2][y] = true;
						start.push(make_pair(x + 2, y));
					}
				}
			}
		}
		if (y != 1) {
			if (plmi(blocks[x][y], blocks[x][y - 1]) == true) {
				if (can_arrive[x][y - 1] == false) {
					can_arrive[x][y - 1] = true;
					start.push(make_pair(x, y - 1));
				}
			}
			if (y != 2) {
				if (blocks[x][y] == blocks[x][y - 2]&&blocks[x][y] > blocks[x][y-1]) {
					if (can_arrive[x][y - 2] == false) {
						can_arrive[x][y - 2] = true;
						start.push(make_pair(x, y - 2));
					}
				}
			}
		}
		if (y != w) {
			if (plmi(blocks[x][y], blocks[x][y + 1]) == true) {
				if (can_arrive[x][y + 1] == false) {
					can_arrive[x][y + 1] = true;
					start.push(make_pair(x, y + 1));
				}
			}
			if (y + 1 != w) {
				if (blocks[x][y] == blocks[x][y + 2]&&blocks[x][y] > blocks[x][y+1]) {
					if (can_arrive[x][y + 2] == false) {
						can_arrive[x][y + 2] = true;
						start.push(make_pair(x, y + 2));
					}
				}
			}
		}
	}
	if (can_arrive[goalx][goaly] == true) {
		cout << "YES" << endl;
	}
	else {
		cout << "NO" << endl;
	}
	return 0;
}