#include <iostream>
#include <string>
using namespace std;
int main(void) {
	string s;
	cin >> s;
	string ans = "NA";
	if (s.size() >= 3) {
		for (int i = 0; i < s.size() - 2; ++i) {
			if (s.substr(i, 3) == "OOO") {
				ans = "East";
				break;
			}
			else if (s.substr(i, 3) == "XXX") {
				ans = "West";
				break;
			}
		}
	}
	cout << ans << endl;
	return 0;
}