#include <iostream>
using namespace std;

int main() {
	char s[100];
	int west = 0,east = 0;
	for (int i = 0;i < 100;i++) {
		cin >> s[i];
		if (s[i] == 'O') {
			east++;
			west = 0;
		}
		else if (s[i] == 'X'){
			west++;
			east = 0;
		}
		if (east >= 3) {
			cout << "East" << endl;
			return 0;
		}
		if (west >= 3) {
			cout << "West" << endl;
			return 0;
		}
	}
	cout << "NA" << endl;
}