#include <bits/stdc++.h>
using namespace std;

int main() {
	string s;
	cin >> s;

	string w = "NA";
	int sl = s.size();
	if (sl < 3) {
		cout << w << endl;
		return 0;
	}
	else {
		for (int i = 0; i < sl - 2; i++) {
			if (s.substr(i, 3) == "OOO") {
				w = "East";
				break;
			}
			else if (s.substr(i, 3) == "XXX") {
				w = "West";
				break;
			}
		}

		cout << w << endl;
	}
}