//inlclude前用define 
#define _USE_MATH_DEFINES

//include
#include<iostream>
#include<string>
#include<algorithm>
#include<vector>
#include<cmath>

using namespace std;
//typedef
typedef vector<int> VI;
typedef vector<string> VS;
typedef vector<char> VC;

int main() {
	string s;
	cin >> s;
	int east = 0;
	int west = 0;
	int size = s.size();
	for (int i = 0; i < size; i++) {
		if (s[i] == 'O') {
			east++;
			west = 0;
		} else if (s[i] == 'X') {
			west++;
			east = 0;
		}

		if (west == 3) {
			cout << "West" << endl;
			return 0;
		} else if(east==3){
			cout << "East" << endl;
			return 0;
		}

	}
	cout << "NA" << endl;
	return 0;
}