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

class Program
{
    static void Main(string[] args)
    {
        string s = Console.ReadLine();
        int eFlg = 0;
        int wFlg = 0;
        string ans = "NA";

        if (s.Contains("OOO"))
        {
            eFlg = 1;
        }

        if (s.Contains("XXX"))
        {
            wFlg = 1;
        }

        if (eFlg == 1 && wFlg == 1)
        {
            if (s.IndexOf("OOO") < s.IndexOf("XXX"))
            {
                ans = "East";
            }
            else
            {
                ans = "West";
            }
        }
        else if (eFlg == 1)
        {
            ans = "East";
        }
        else if (wFlg == 1)
        {
            ans = "West";
        }

        Console.WriteLine(ans);
        Console.Read();
    }
}