import java.util.*;

class Main {
    public static void main(String[] args) {
        Scanner in = new Scanner(System.in);
        String s = in.next();

        String ans = "NA";

        if(s.length() >= 3) {
            for(int i=1; i<s.length()-1; i++) {
                char c1 = s.charAt(i-1);
                char c2 = s.charAt(i);
                char c3 = s.charAt(i+1);
                if(c1 == 'O' && c2 == 'O' && c3 == 'O') {
                    ans = "East";
                    break;
                }
                if(c1 == 'X' && c2 == 'X' && c3 == 'X') {
                    ans = "West";
                    break;
                }
            }
        }

        System.out.println(ans);
    }
}