#include <iostream>
#include <stdio.h>
#include <algorithm>
#include <vector>
#include <cmath>
#include <string>
#include <sstream>
#include<sstream>
#include <queue>
#include <limits>
#include <cstdlib>
#include <deque>
#include <map>
#include <set>
using namespace std;

int main() {

	string s;
	cin>>s;

	int east =0;
	int west =0;

	bool judge =true;

	for(int i=0; i<s.length(); i++){
		if(s[i] == 'O'){
			east++;
			west=0;
		}else {
			west++;
			east=0;
		}
		if(east == 3){
			cout<<"East"<<endl;
			judge = false;
			break;
		}
		if(west == 3){
			cout<<"West"<<endl;
			judge = false;
			break;
		}
	}
	if(judge){
	cout<<"NA"<<endl;
	}
	return 0;
}