#include <cctype>
#include <cerrno>
#include <cfloat>
#include <ciso646>
#include <climits>
#include <clocale>
#include <cmath>
#include <csetjmp>
#include <csignal>
#include <cstdarg>
#include <cstddef>
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <ctime>

// C++
#include <algorithm>
#include <bitset>
#include <complex>
#include <deque>
#include <exception>
#include <fstream>
#include <functional>
#include <iomanip>
#include <ios>
#include <iosfwd>
#include <iostream>
#include <istream>
#include <iterator>
#include <limits>
#include <list>
#include <locale>
#include <map>
#include <memory>
#include <new>
#include <numeric>
#include <ostream>
#include <queue>
#include <set>
#include <sstream>
#include <stack>
#include <stdexcept>
#include <streambuf>
#include <string>
#include <typeinfo>
#include <utility>
#include <valarray>
#include <vector>

#include <unordered_set>
#include <unordered_map>

using namespace std;

#define all(c) ((c).begin()), ((c).end())
#define dump(c) cerr << "> " << #c << " = " << (c) << endl;
#define iter(c) __typeof((c).begin())
#define tr(i, c) for (iter(c) i = (c).begin(); i != (c).end(); i++)
#define REP(i, a, b) for (int i = a; i < (int)(b); i++)
#define rep(i, n) REP(i, 0, n)
#define mp make_pair
#define fst first
#define snd second
#define pb push_back
#define debug(fmt, ...) \
        fprintf( stderr, \
                  fmt "\n", \
                  ##__VA_ARGS__ \
        )

typedef unsigned int uint;
typedef long long ll;
typedef unsigned long long ull;
typedef vector<int> vi;
typedef vector<ll> vll;
typedef vector<vll> vvll;
typedef vector<vi> vvi;
typedef vector<double> vd;
typedef vector<vd> vvd;
typedef vector<string> vs;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;

const int INF = 1 << 30;
const double EPS = 1e-10;

double zero(double d) {
    return d < EPS ? 0.0 : d;
}

template<class T>
bool chmax(T &a, const T &b) {
    if (a < b) {
        a = b;
        return true;
    }
    return false;
}

template<class T>
bool chmin(T &a, const T &b) {
    if (b < a) {
        a = b;
        return true;
    }
    return false;
}

#define UNIQUE(v) v.erase( unique(v.begin(), v.end()), v.end() );

template<typename T1, typename T2>
ostream &operator<<(ostream &os, const pair<T1, T2> &p) {
    return os << '(' << p.first << ',' << p.second << ')';
}

template<typename T>
ostream &operator<<(ostream &os, const vector<T> &a) {
    os << '[';
    rep(i, a.size()) os << (i ? " " : "") << a[i];
    return os << ']';
}

string toString(int i) {
    stringstream ss;
    ss << i;
    return ss.str();
}

const int MOD = 1000000007;

// a^k
ll fpow(ll a, ll k, int M) {
    ll res = 1ll;
    ll x = a;
    while (k != 0) {
        if ((k & 1) == 1)
            res = (res * x) % M;
        x = (x * x) % M;
        k >>= 1;
    }
    return res;
}

struct prepare {
    prepare() {
        cout.setf(ios::fixed, ios::floatfield);
        cout.precision(8);
        ios_base::sync_with_stdio(false);
    }
} _prepare;

int main() {
    int h, w;
    cin >> h >> w;
    int sr, sc, gr, gc;
    cin >> sr >> sc >> gr >> gc;
    --sr, --sc, --gr, --gc;

    vvi field(h, vi(w));
    rep(r, h) {
        rep(c, w) {
            char tmp;
            cin >> tmp;
            field[r][c] = tmp - '0';
        }
    }

    vector<vector<bool> > used(h, vector<bool>(w, false));
    queue<int> que;

    que.push(sr * w + sc);
    used[sr][sc] = true;

    const int dr[] = {1, 0, -1, 0};
    const int dc[] = {0, -1, 0, 1};

    const int dr2[] = {2, 0, -2, 0};
    const int dc2[] = {0, -2, 0, 2};

    while (!que.empty()) {
        int _t = que.front();
        que.pop();
        int r = _t / w;
        int c = _t % w;

        if (r == gr && c == gc) {
            cout << "YES" << endl;
            return 0;
        }

        rep(i, 4) {
            int nr = r + dr[i];
            int nc = c + dc[i];

            if (0 <= nr && nr < h && 0 <= nc && nc < w &&
                !used[nr][nc] &&
                abs(field[r][c] - field[nr][nc]) <= 1) {
                que.push(nr * w + nc);
                used[nr][nc] = true;
            }

            int nr2 = r + dr2[i];
            int nc2 = c + dc2[i];
            if (0 <= nr2 && nr2 < h && 0 <= nc2 && nc2 < w &&
                !used[nr2][nc2] &&
                field[r][c] == field[nr2][nc2] &&
                field[r][c] > field[nr][nc]) {
                que.push(nr2 * w + nc2);
                used[nr2][nc2] = true;
            }
        }
    }

    cout << "NO" << endl;

    return 0;
}