#include <iostream>
#include <vector>
#include <string>
#include <queue>

template <class T>
std::vector<T> vec(int len, T elem) { return std::vector<T>(len, elem); }

const std::vector<int> dx{-1, 1, 0, 0}, dy{0, 0, -1, 1};

void solve() {
    int h, w, sx, sy, gx, gy;
    std::cin >> h >> w >> sx >> sy >> gx >> gy;
    --sx, --sy, --gx, --gy;

    auto pss = vec(h, vec(w, 0));
    for (auto& ps : pss) {
        for (auto& p : ps) {
            char c;
            std::cin >> c;
            p = c - '0';
        }
    }

    auto outer = [&](int x, int y) {
        return x < 0 || h <= x || y < 0 || w <= y;
    };

    auto visited = vec(h, vec(w, false));
    visited[sx][sy] = true;
    std::queue<std::pair<int, int>> que;
    que.emplace(sx, sy);

    while (!que.empty()) {
        auto [x, y] = que.front();
        que.pop();

        for (int d = 0; d < 4; ++d) {
            int nx = x + dx[d],
                ny = y + dy[d];

            if (outer(nx, ny) ||
                std::abs(pss[x][y] - pss[nx][ny]) > 1 ||
                visited[nx][ny]) continue;
            visited[nx][ny] = true;
            que.emplace(nx, ny);
        }

        for (int d = 0; d < 4; ++d) {
            int nx = x + dx[d],
                ny = y + dy[d];

            if (outer(nx, ny) ||
                pss[nx][ny] >= pss[x][y]) continue;

            nx += dx[d], ny += dy[d];
            if (outer(nx, ny) ||
                pss[nx][ny] != pss[x][y] ||
                visited[nx][ny]) continue;

            visited[nx][ny] = true;
            que.emplace(nx, ny);
        }
    }

    std::cout << (visited[gx][gy] ? "YES" : "NO") << "\n";
}

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

    solve();

    return 0;
}