#include <bits/stdc++.h>
using namespace std;
#define FOR(i,n) for(int (i)=0;(i)<(int)(n);++(i))
#define FORR(i,l,n) for(int (i)=l;(i)<(int)(n);++(i))
void solve() {
	std::string S;
	cin >> S;
	int east = S.find("OOO");
	int west = S.find("XXX");
	if (east == string::npos && west == string::npos) {
		std::cout << "NA" << std::endl;
	}
	else if (string::npos != east &&  east < west || west == string::npos) {
		std::cout << "East" << std::endl;
	}
	else if (string::npos != west && west < east || east == string::npos) {
		std::cout << "West" << std::endl;
	}
}
int main() {
	ios::sync_with_stdio(false);
	solve();
	return 0;
}