import java.util.Scanner;
public class Main{
	private static Scanner sc=new Scanner(System.in);
	public static void main(String args[])throws Exception{
		String s=sc.nextLine();
		if(s.indexOf("OOO")==-1 && s.indexOf("XXX")==-1)
			System.out.println("NA");
		else if(s.indexOf("OOO")==-1)
			System.out.println("West");
		else if(s.indexOf("XXX")==-1)
			System.out.println("East");
		else if(s.indexOf("OOO")<s.indexOf("XXX"))
			System.out.println("East");
		else
			System.out.println("West");
	}
}