#define _USE_MATH_DEFINES

#include <iostream>	//cin, cout
#include <vector>	//vector
#include <algorithm> //sort,min,max,count
#include <string>	//string,getline
#include <ios>		//fixed
#include <iomanip>	//setprecision
#include <utility> //swap
#include <cstdlib>	//abs(int)
#include <cmath>	//sqrt
#include <sstream>	//stringstream,getline
#include <cmath>	//ceil,M_PI
#include <numeric>	//gcd

using namespace std;

int main() {

	string S;
	cin >> S;

	int e = S.find("OOO");
	int w = S.find("XXX");

	if (e == w) {
		cout << "NA" << endl;
		return 0;
	}

	if (e < w && e != -1) {
		cout << "East" << endl;
	}
	else {
		cout << "West" << endl;
	}

	return 0;

}