import java.util.*;

public class Main {
  public static void main(String[] args) {
    Scanner sc = new Scanner(System.in);
    String s = sc.next();
    int east = 200;
    int west = 200;
    for(int i = 0; i < s.length() - 2; i++) {
      if((s.charAt(i) == 'O') && (s.charAt(i + 1) == 'O') && (s.charAt(i + 2) == 'O') && (east == 200)) east = i;
      if((s.charAt(i) == 'X') && (s.charAt(i + 1) == 'X') && (s.charAt(i + 2) == 'X') && (west == 200)) west = i;
    }
    String ans = "NA";
    if(east > west) ans = "West";
    if(east < west) ans = "East";
    System.out.println(ans);
  }
}