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

namespace Test
{
    class Program
    {
        static void Main(string[] args)
        {
            string s = Console.ReadLine();
            string ret = "";
            for (int i = 0; i <= s.Length - 3; i++)
            {
                if (s.Substring(i,3) == "ooo" && ret == "")
                {
                    ret = "East";
                }
                else if (s.Substring(i,3) == "xxx" && ret == "")
                {
                    ret = "West";
                }
            }
            Console.WriteLine(ret == "" ? "NA" : ret);
        }
    }
}