open System
open System.Collections.Generic

[<AutoOpen>]
module Cin =
    let read f = stdin.ReadLine() |> f
    let reada f = stdin.ReadLine().Split() |> Array.map f
    let readChars() = read string |> Seq.toArray
    let readInts() = readChars() |> Array.map (fun x -> Convert.ToInt32(x.ToString()))

[<AutoOpen>]
module Cout =
    let writer = new IO.StreamWriter(new IO.BufferedStream(Console.OpenStandardOutput()))
    let print (s: string) = writer.Write s
    let println (s: string) = writer.WriteLine s
    let inline puts (s: ^a) = string s |> println

let solve() =
    let s = readChars()
    seq {
        for i in 0 .. s.Length - 3 do
            let a = sprintf "%c%c%c" s.[i] s.[i + 1] s.[i + 2]
            if a = "OOO" then yield "West"
            elif a = "XXX" then yield "East"

    }
    |> fun s ->
        if Seq.isEmpty s then "NA" else Seq.head s
    |> puts

[<EntryPoint>]
let main _ =
    try
        solve()
    with e -> printfn "%s" (e.ToString())
    writer.Close()
    0 // return an integer exit code