#define _CRT_SECURE_NO_WARNINGS
#define _USE_MATH_DEFINES

#include <bits/stdc++.h>
using namespace std;
using i32 = int32_t; using i64 = int64_t; using f64 = double_t; using str = string;
template <typename T> using vec = vector<T>;
template <typename T> using heap = priority_queue<T, vec<T>, greater<T>>;
#define times(n, i) for (i32 i = 0; i < (n); ++i)
#define range(n, m, i) for (i32 i = (n); i < (m); ++i)
#define upto(n, m, i) for (i32 i = (n); i <= (m); ++i)
#define downto(n, m, i) for (i32 i = (n); i >= (m); --i)
#define foreach(xs, x) for (auto &x : (xs))
#define all(xs) (xs).begin(), (xs).end()
#define sortall(xs) sort(all(xs))
#define reverseall(xs) reverse(all(xs))
#define uniqueall(xs) (xs).erase(unique(all(xs)), (xs).end())
#define maximum(xs) (*max_element(all(xs)))
#define minimum(xs) (*min_element(all(xs)))
#define even(x) (((x) & 1) == 0)
#define odd(x) (((x) & 1) == 1)
#define append emplace_back
const i64 MOD = 1000000007;

i32 h, w, sx, sy, gx, gy;
i32 m[50][50];
bool fp[50][50];
i32 ox[4] = { -1, 0, 1, 0 };
i32 oy[4] = { 0, -1, 0, 1 };

bool rec(i32 x, i32 y) {
    fp[x][y] = true;

    if (x == gx && y == gy)
        return true;

    times(4, i) {
        i32 nx = x+ox[i], ny = y+oy[i];
        if (0 <= nx && nx < w && 0 <= ny && ny < h) {
            if (!fp[nx][ny] && abs(m[nx][ny] - m[x][y]) <= 1) {
                fp[nx][ny] = true;
                if (rec(nx, ny))
                    return true;
            }
        }
        i32 mx = x + ox[i]*2, my = y + oy[i]*2;
        if (0 <= mx && mx < w && 0 <= my && my < h) {
            if (!fp[mx][my] && m[mx][my] == m[x][y] && m[nx][ny] < m[x][y]) {
                fp[mx][my] = true;
                if (rec(mx, my))
                    return true;
            }
        }
    }

    return false;
}

i32 main()
{
    cin >> h >> w >> sy >> sx >> gy >> gx;
    sy--; sx--; gy--; gx--;

    times(h, i) {
        str s; cin >> s;
        times(w, j) {
            m[j][i] = s[j]-'0';
        }
    }

    cout << (rec(sx, sy) ? "YES" : "NO") << endl;
    return 0;
}