#include <iostream>
#include <vector>
#include <algorithm>
#include <cmath>
#include <queue>
#include <string>
#include <map>
#include <set>
#include <stack>
#include <tuple>
#include <deque>
#include <array>
#include <numeric>
#include <bitset>
#include <iomanip>
#include <cassert>
#include <chrono>
#include <random>
#include <limits>
#include <iterator>
#include <functional>
#include <sstream>
#include <fstream>
#include <complex>
#include <cstring>
#include <unordered_map>
#include <unordered_set>
using namespace std;

using ll = long long;
using P = pair<int, int>;
constexpr int INF = 1001001001;
constexpr int mod = 1000000007;
// constexpr int mod = 998244353;

template<class T>
inline bool chmax(T& x, T y){
    if(x < y){
        x = y;
        return true;
    }
    return false;
}
template<class T>
inline bool chmin(T& x, T y){
    if(x > y){
        x = y;
        return true;
    }
    return false;
}

constexpr int dx[4] = {1, 0, -1, 0};
constexpr int dy[4] = {0, 1, 0, -1};

int main(){
    ios::sync_with_stdio(false);
    cin.tie(nullptr);

    int h, w, sx, sy, tx, ty;
    cin >> h >> w >> sx >> sy >> tx >> ty;
    --sx, --sy, --tx, --ty;
    vector<vector<int>> grid(h, vector<int>(w));
    for(int i = 0; i < h; ++i){
        for(int j = 0; j < w; ++j){
            char ch;
            cin >> ch;
            grid[i][j] = ch - '0';
        }
    }

    vector<vector<bool>> used(h, vector<bool>(w));
    queue<P> que;
    que.emplace(sx, sy);
    used[sx][sy] = true;
    while(!que.empty()){
        auto [x, y] = que.front();
        que.pop();
        for(int i = 0; i < 4; ++i){
            int nx = x + dx[i], ny = y + dy[i];
            if(nx < 0 || nx >= h || ny < 0 || ny >= w)  continue;
            if(!used[nx][ny] && abs(grid[nx][ny] - grid[x][y]) <= 1){
                que.emplace(nx, ny);
                used[nx][ny] = true;
            }
            nx += dx[i], ny += dy[i];
            if(nx < 0 || nx >= h || ny < 0 || ny >= w || used[nx][ny])  continue;
            if(grid[nx][ny] == grid[x][y] && grid[nx - dx[i]][ny - dy[i]] < grid[x][y]){
                que.emplace(nx, ny);
                used[nx][ny] = true;
            }
        }
    }

    cout << (used[tx][ty] ? "YES\n" : "NO\n");

    return 0;
}