module Main
open System

let s = [ for c in Console.ReadLine() -> c]

let rec calc = function
    | w :: x :: y :: zs when w = x && x = y && y = 'O' -> "East"
    | w :: x :: y :: zs when w = x && x = y -> "West"
    | _ :: zs -> calc zs
    | _ -> "NA"

Console.WriteLine(calc s)