import java.util.*;

public class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        String S = sc.next();
        System.out.println(f(S));
    }
    static String f(String S){
        int x = S.indexOf("OOO");
        int y = S.indexOf("XXX");
        if(x==-1){
            if(y==-1){
                return "NA";
            }else{
                return "West";
            }
        }else{
            if(y==-1||x<y){
                return "East";
            }else{
                return "West";
            }
        }
    }
}