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

int H, W, Sx, Sy, Gx, Gy;
vector<string> B(51);
bool dp[51][51] = {{0}};

void rec(int x = Sx - 1, int y = Sy - 1, int high = B[Sy - 1][Sx - 1] - '0'){
    
    if(x <= -1 || x >= W || y <= -1 || y >= H) return;
    if(high != B[y][x] - '0') return;
    if(x == Gx - 1 && y == Gy- 1){
        cout << "YES" << endl;
        exit(0);
    }
    
    if(dp[y][x]) return;
    dp[y][x] = true;
    
    rec(x - 1, y, high);
    rec(x + 1, y, high);
    rec(x, y - 1, high);
    rec(x, y + 1, high);
    
    rec(x - 1, y, high + 1);
    rec(x + 1, y, high + 1);
    rec(x, y - 1, high + 1);
    rec(x, y + 1, high + 1);
    
    rec(x - 1, y, high - 1);
    rec(x + 1, y, high - 1);
    rec(x, y - 1, high - 1);
    rec(x, y + 1, high - 1);
    
    if(x - 1 >= 0 && high > B[y][x - 1] - '0') rec(x - 2, y, high);
    if(x + 1 >= 0 && high > B[y][x + 1] - '0') rec(x + 2, y, high);
    if(y - 1 >= 0 && high > B[y - 1][x] - '0') rec(x, y - 2, high);
    if(y + 1 >= 0 && high > B[y + 1][x] - '0') rec(x, y + 2, high);
    
    return;
}

int main(void){
    
    cin >> H >> W >> Sy >> Sx >> Gy >> Gx;
    for(int i = 0; i < H; ++i) cin >> B[i];
    
    rec();
    cout << "NO" << endl;
    
    return 0;
}