using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace YukiCoder
{
    class Program
    {
        static void Main(string[] args)
        {
            string S = Console.ReadLine();
            int East = S.IndexOf("OOO");
            int West = S.IndexOf("XXX");
            if (East < 0) East = 100;
            if (West < 0) West = 100;
            S = (East < West) ? "East" : (West < East) ? "West" : "NA";
            Console.WriteLine(S);
            //Console.ReadLine();
        }
    }
}