/* package whatever; // don't place package name! */

import java.util.*;
import java.lang.*;
import java.io.*;

/* Name of the class has to be "Main" only if the class is public. */
class Main
{
    
    
    public static void main (String[] args) throws java.lang.Exception
    {
        // your code goes here
        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
        String line = br.readLine();
        int east = 0;
        int west = 0;
        for(int i=0;i<line.length();i++){
            char c = line.charAt(i);
            switch(c){
            case 'O':
                west=0;
                ++east;
                break;
            case 'X':
                east=0;
                ++west;
                break;
            }
            if(east>=3){
                System.out.println("East");
                return;
            }
            if(west>=3){
                System.out.println("West");
                return;
            }
        }
        System.out.println("NA");
    }
}