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

class Program
{
    static void Main(string[] args)
    {
        char[] A = Console.ReadLine().ToCharArray();

        int west = 0;
        int east = 0;
        int count = 0;
        for (int i = 0; i < A.Length; i++)
        {
            if (A[i] == 'O')
            {
                east++;

                if (east == 3)
                {
                    System.Console.WriteLine("East");
                    return;
                }

                west = 0;
            }
            else
            {
                west++;
                if (west == 3)
                {
                    System.Console.WriteLine("West");
                    return;
                }
                east = 0;
            }
        }

        System.Console.WriteLine("NA");
    }
}