import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;

public class No486 {
	public static void main(String[] args) throws IOException{
		String str = new BufferedReader(new InputStreamReader(System.in)).readLine();
		char[] syohai = str.toCharArray();
		judge(syohai);
	}
	
	public static void judge(char[] chr){
		int eastV = 0;
		int westV = 0;
		for(int i=0; i<chr.length; i++){
			if(chr[i] == 'O'){
				eastV++;
				westV = 0;
			} else if(chr[i] == 'X'){
				westV++;
				eastV = 0;
			}
			if(eastV == 3) {
				System.out.println("East");
				break;
			} else if(westV == 3) {
				System.out.println("West");
				break;
			}
		}
		if(eastV != 3 && westV != 3) System.out.println("NA");
	}
}