open System

let () =
    let h, w = stdin.ReadLine () |>
               (fun l -> l.Split ()) |>
               (fun arr -> (int arr.[0], int arr.[1]))
    let sx, sy, gx, gy = stdin.ReadLine () |>
                         (fun l -> l.Split ()) |>
                         (fun arr -> (int arr.[0], int arr.[1],
                                      int arr.[2], int arr.[3]))

    let mapArr = Array2D.zeroCreateBased<int> 1 1 w h

    let readB (x, line:string) =
        seq {1..w} |> Seq.iter (fun y -> mapArr.[y, x] <- int line.[y - 1] - int '0')

    seq { for x in 1..h -> (x, stdin.ReadLine ()) } |> Seq.iter readB


    let searchPath startY startX =
        let dxy = [(1, 0); (-1, 0); (0, 1); (0, -1)]
        
        let canMove1 (cy, cx) (dy, dx) =
            let y, x = cy + dy, cx + dx

            y >= 1 && y <= w && x >= 1 && x <= h &&
            abs(mapArr.[y, x] - mapArr.[cy, cx]) <= 1

        let canMove2 (cy, cx) (dy, dx) =
            let y1, y2 = cy + dy, cy + dy * 2
            let x1, x2 = cx + dx, cx + dx * 2

            y2 >= 1 && y2 <= w && x2 >= 1 && x2 <= h &&
            mapArr.[cy, cx] = mapArr.[y2, x2] &&
            mapArr.[cy, cx] > mapArr.[y1, x1]

        let rec searchPath' lst chkedSet =
            match lst with
            | [] -> false
            | pos::rest ->
                let cy, cx = pos
                let cand1 = List.filter (canMove1 (cy, cx)) dxy
                let cand2 = List.filter (canMove2 (cy, cx)) dxy |>
                            List.map (fun (dy, dx) -> (dy * 2, dx * 2))
                let cand = List.append cand1 cand2
                let candLst = List.map (fun (dy, dx) -> (cy + dy, cx + dx)) cand

                if List.contains (gy, gx) candLst then true
                else
                    let nextLst = List.append candLst rest |>
                                  List.filter (fun pos -> not (Set.contains pos chkedSet))
                    let nextChkedSet = Set.add (cy, cx) chkedSet

                    searchPath' nextLst nextChkedSet
        
        if startY = gy && startX = gx then true
        else searchPath' [(startY, startX)] Set.empty

    searchPath sy sx |> (function | true -> "YES" | false -> "NO") |> printfn "%s"