package puzzle.yukicoder.threedimensionalmaze;

import java.util.ArrayList;
import java.util.List;
import java.util.Scanner;

public class ThreeDimensionalMaze {

    private static int[][] maze;

    private static boolean[][] reached;

    /* シンプルにルールに基づき、スタートから移動可能な場所をチェックしつつ幅優先探索する */
    public static void main(String[] args) {
        Scanner cin = new Scanner(System.in);
        int h = Integer.parseInt(cin.next());
        int w = Integer.parseInt(cin.next());
        int[] start = new int[2];
        start[0] = Integer.parseInt(cin.next()) - 1;
        start[1] = Integer.parseInt(cin.next()) - 1;
        int[] goal = new int[2];
        goal[0] = Integer.parseInt(cin.next()) - 1;
        goal[1] = Integer.parseInt(cin.next()) - 1;
        maze = new int[h][w];
        reached = new boolean[h][w];
        for (int i = 0; i < h; i++) {
            String[] lines = cin.next().split("");
            for (int j = 0; j < w; j++) {
                maze[i][j] = Integer.parseInt(lines[j]);
            }
        }
        cin.close();
        List<int[]> currentBlocks = new ArrayList<int[]>();
        List<int[]> nextBlocks = new ArrayList<int[]>();
        currentBlocks.add(start);
        reached[start[0]][start[1]] = true;
        while (!currentBlocks.isEmpty()) {
            for (int[] block : currentBlocks) {
                /* 上1ブロック */
                if (block[0] > 0 && !reached[block[0] - 1][block[1]]
                        && (maze[block[0] - 1][block[1]] >= maze[block[0]][block[1]] - 1 && maze[block[0] - 1][block[1]] <= maze[block[0]][block[1]] + 1)) {
                    nextBlocks.add(new int[] {block[0] - 1, block[1]});
                    reached[block[0] - 1][block[1]] = true;
                }
                /* 上2ブロック */
                if (block[0] > 1 && !reached[block[0] - 2][block[1]] && maze[block[0] - 2][block[1]] == maze[block[0]][block[1]] && maze[block[0] - 1][block[1]] < maze[block[0]][block[1]]) {
                    nextBlocks.add(new int[] {block[0] - 2, block[1]});
                    reached[block[0] - 2][block[1]] = true;
                }
                /* 下1ブロック */
                if (block[0] < h - 1 && !reached[block[0] + 1][block[1]]
                        && (maze[block[0] + 1][block[1]] >= maze[block[0]][block[1]] - 1 && maze[block[0] + 1][block[1]] <= maze[block[0]][block[1]] + 1)) {
                    nextBlocks.add(new int[] {block[0] + 1, block[1]});
                    reached[block[0] + 1][block[1]] = true;
                }
                /* 下2ブロック */
                if (block[0] < h - 2 && !reached[block[0] + 2][block[1]] && maze[block[0] + 2][block[1]] == maze[block[0]][block[1]] && maze[block[0] + 1][block[1]] < maze[block[0]][block[1]]) {
                    nextBlocks.add(new int[] {block[0] + 2, block[1]});
                    reached[block[0] + 2][block[1]] = true;
                }
                /* 右1ブロック */
                if (block[1] > 0 && !reached[block[0]][block[1] - 1]
                        && (maze[block[0]][block[1] - 1] >= maze[block[0]][block[1]] - 1 && maze[block[0]][block[1] - 1] <= maze[block[0]][block[1]] + 1)) {
                    nextBlocks.add(new int[] {block[0], block[1] - 1});
                    reached[block[0]][block[1] - 1] = true;
                }
                /* 右2ブロック */
                if (block[1] > 1 && !reached[block[0]][block[1] - 2] && maze[block[0]][block[1] - 2] == maze[block[0]][block[1]] && maze[block[0]][block[1] - 1] < maze[block[0]][block[1]]) {
                    nextBlocks.add(new int[] {block[0], block[1] - 2});
                    reached[block[0]][block[1] - 2] = true;
                }
                /* 左1ブロック */
                if (block[1] < w - 1 && !reached[block[0]][block[1] + 1]
                        && (maze[block[0]][block[1] + 1] >= maze[block[0]][block[1]] - 1 && maze[block[0]][block[1] + 1] <= maze[block[0]][block[1]] + 1)) {
                    nextBlocks.add(new int[] {block[0], block[1] + 1});
                    reached[block[0]][block[1] + 1] = true;
                }
                /* 左2ブロック */
                if (block[1] < w - 2 && !reached[block[0]][block[1] + 2] && maze[block[0]][block[1] + 2] == maze[block[0]][block[1]] && maze[block[0]][block[1] + 1] < maze[block[0]][block[1]]) {
                    nextBlocks.add(new int[] {block[0], block[1] + 2});
                    reached[block[0]][block[1] + 2] = true;
                }
            }
            if (reached[goal[0]][goal[1]]) {
                exit(true);
            }
            currentBlocks = nextBlocks;
            nextBlocks = new ArrayList<int[]>();
        }
        exit(false);
    }

    private static void exit(boolean result) {
        if (result) {
            System.out.println("YES");
        } else {
            System.out.println("NO");
        }
        System.exit(0);
    }

}