import java.io.IOException; import java.io.InputStream; import java.util.ArrayList; import java.util.List; import java.util.NoSuchElementException; public class Main { private static int[][] map; private static boolean[][] visited; private static int h; private static int w; private static int gx; private static int gy; public static void main(String[] args) { FastScanner sc = new FastScanner(); h = sc.nextInt(); w = sc.nextInt(); int sy = sc.nextInt() - 1; int sx = sc.nextInt() - 1; gy = sc.nextInt() - 1; gx = sc.nextInt() - 1; map = new int[h][w]; for (int i = 0; i < h; i++) { char[] m = sc.next().toCharArray(); for (int j = 0; j < w; j++) { map[i][j] = m[j] - '0'; } } visited = new boolean[h][w]; boolean ret = dfs(sx, sy); System.out.println(ret ? "YES" : "NO"); } private static boolean dfs(int x, int y) { if (visited[y][x]) return false; if (x == gx && y == gy) return true; visited[y][x] = true; int now = map[y][x]; if (x > 0 && Math.abs(map[y][x - 1] - now) <= 1 && dfs(x - 1, y)) return true; if (y > 0 && Math.abs(map[y - 1][x] - now) <= 1 && dfs(x, y - 1)) return true; if (x < w - 1 && Math.abs(map[y][x + 1] - now) <= 1 && dfs(x + 1, y)) return true; if (y < h - 1 && Math.abs(map[y + 1][x] - now) <= 1 && dfs(x, y + 1)) return true; if (x > 1 && map[y][x - 2] == now && dfs(x - 2, y)) return true; if (y > 1 && map[y - 2][x] == now && dfs(x, y - 2)) return true; if (x < w - 2 && map[y][x + 2] == now && dfs(x + 2, y)) return true; if (y < h - 2 && map[y + 2][x] == now && dfs(x, y + 2)) return true; return false; } } class Graph { public static class Path implements Comparable { public final int from; public final int to; public final long cost; public Path(int from, int to, long cost) { this.from = from; this.to = to; this.cost = cost; } @Override public int compareTo(Path o) { return Long.compare(this.cost, o.cost); } } private final List> edgeList; private final int size; public Graph(int n) { this.size = n; this.edgeList = new ArrayList>(); for (int i = 0; i < n; i++) { this.edgeList.add(new ArrayList()); } } public void add(int from, int to, long cost) { this.edgeList.get(from).add(new Path(from, to, cost)); } public void addBoth(int v1, int v2, long cost) { this.add(v1, v2, cost); this.add(v2, v1, cost); } public void add(int from, int to) { this.edgeList.get(from).add(new Path(from, to, 1)); } public void addBoth(int v1, int v2) { this.add(v1, v2, 1); this.add(v2, v1, 1); } public List get(int from) { return this.edgeList.get(from); } public int size() { return this.size; } } class FastScanner { public static String debug = null; private final InputStream in = System.in; private int ptr = 0; private int buflen = 0; private byte[] buffer = new byte[1024]; private boolean eos = false; private boolean hasNextByte() { if (ptr < buflen) { return true; } else { ptr = 0; try { if (debug != null) { buflen = debug.length(); buffer = debug.getBytes(); debug = ""; eos = true; } else { buflen = in.read(buffer); } } catch (IOException e) { e.printStackTrace(); } if (buflen < 0) { eos = true; return false; } else if (buflen == 0) { return false; } } return true; } private int readByte() { if (hasNextByte()) return buffer[ptr++]; else return -1; } private static boolean isPrintableChar(int c) { return 33 <= c && c <= 126; } private void skipUnprintable() { while (hasNextByte() && !isPrintableChar(buffer[ptr])) ptr++; } public boolean isEOS() { return this.eos; } public boolean hasNext() { skipUnprintable(); return hasNextByte(); } public String next() { if (!hasNext()) throw new NoSuchElementException(); StringBuilder sb = new StringBuilder(); int b = readByte(); while (isPrintableChar(b)) { sb.appendCodePoint(b); b = readByte(); } return sb.toString(); } public long nextLong() { if (!hasNext()) throw new NoSuchElementException(); long n = 0; boolean minus = false; int b = readByte(); if (b == '-') { minus = true; b = readByte(); } if (b < '0' || '9' < b) { throw new NumberFormatException(); } while (true) { if ('0' <= b && b <= '9') { n *= 10; n += b - '0'; } else if (b == -1 || !isPrintableChar(b)) { return minus ? -n : n; } else { throw new NumberFormatException(); } b = readByte(); } } public int nextInt() { return (int) nextLong(); } public long[] nextLongList(int n) { return nextLongTable(1, n)[0]; } public int[] nextIntList(int n) { return nextIntTable(1, n)[0]; } public long[][] nextLongTable(int n, int m) { long[][] ret = new long[n][m]; for (int i = 0; i < n; i++) { for (int j = 0; j < m; j++) { ret[i][j] = nextLong(); } } return ret; } public int[][] nextIntTable(int n, int m) { int[][] ret = new int[n][m]; for (int i = 0; i < n; i++) { for (int j = 0; j < m; j++) { ret[i][j] = nextInt(); } } return ret; } }