#include<cstdio>
#include<cstdlib>
#include<cstring>
#include<cmath>
//#include<cctype>
#include<climits>
#include<iostream>
#include<string>
#include<vector>
#include<map>
//#include<list>
#include<queue>
#include<deque>
#include<algorithm>
//#include<numeric>
#include<utility>
//#include<memory>
#include<functional>
#include<cassert>
#include<set>
#include<stack>
#include<random>

const int dx[] = {1, 0, -1, 0};
const int dy[] = {0, -1, 0, 1};
using namespace std;
typedef long long ll;
typedef unsigned long long ull;
typedef vector<int> vi;
typedef vector<ll> vll;
typedef pair<int, int> pii;

bool done[55][55];
int board[55][55];
string field[55];

int main() {
    cin.tie(0);
    ios::sync_with_stdio(false);
    int H, W;
    cin >> H >> W;
    int sx, sy, gx, gy;
    cin >> sy >> sx >> gy >> gx;
    sy--; sx--; gy--; gx--;
    for (int i = 0; i < H; i++) {
        cin >> field[i];
        for (int j = 0; j < W; j++)
            board[i][j] = field[i][j] - '0';
    }
    queue<pii> que;
    que.push(pii(sy, sx));
    done[sy][sx] = true;
    while (!que.empty()) {
        int y = que.front().first, x = que.front().second;
        que.pop();
        for (int i = 0; i < 4; i++) {
            int ny = y+dy[i], nx = x+dx[i];
            int nny = y+2*dy[i], nnx = x+2*dx[i];
            if (0 <= ny && ny < H && 0 <= nx && nx < W) {
                if (abs(board[y][x] - board[ny][nx]) <= 1) {
                    if (!done[ny][nx]) {
                        que.push(pii(ny, nx));
                        done[ny][nx] = true;
                    }
                }
            }
            if (0 <= nny && nny < H && 0 <= nnx && nnx < W) {
                if (abs(board[y][x] - board[nny][nnx]) <= 0 && board[ny][nx] < board[y][x]) {
                    if (!done[nny][nnx]) {
                        que.push(pii(nny, nnx));
                        done[nny][nnx] = true;
                    }
                }
            }
        }
    }
    if (done[gy][gx]) cout << "YES" << endl;
    else cout << "NO" << endl;
    return 0;
}