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

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

	int east = S.find( "OOO" );
	int west = S.find( "XXX" );
	string ans = "NA";
	if( east != string::npos && west != string::npos ) {
		if( east < west ) ans = "East";
		if( east > west ) ans = "West";
	}
	else if( east != string::npos && west == string::npos ) ans = "East";
	else if( east == string::npos && west != string::npos ) ans = "West";

	cout << ans << endl;
}