#include <iostream>
#include <iomanip>
using namespace std;
 
int main(){
	string S;
	cin >> S;
	bool if_east = false;
	int continuity = 0;
	for(int i = 0; i < S.size(); i++){
		if((if_east && S[i] == 'O') || (!if_east && S[i] == 'X')){
			continuity++;
		}else{
			if_east = (if_east + 1) % 2;
			continuity = 1;
		}
		if(continuity == 3){
			if(if_east){
				cout << "East" << endl;
			}else{
				cout << "West" << endl;
			}
			return 0;
		}
	}
	cout << "NA" << endl;
}