#include <iostream>
#include <string>
int main() {
	std::string S;
	std::cin >> S;
	int W = 0;
	int E = 0;
	int WinFlag = 0;
	bool Flag = false;
	for (int i = 0; i < S.size(); i++) {
		if (S.at(i) == 'O') {
			W++;
			E = 0;
			if (W >= 3 && Flag == false) {
				WinFlag = 1;
				Flag = true;
			}
		}
		if (S.at(i) == 'X') {
			E++;
			W = 0;
			if (E >= 3 && Flag == false) {
				WinFlag = 2;
				Flag = true;
			}
		}
	}

	if (WinFlag == 1) {
		std::cout << "West" << std::endl;
	}
	if (WinFlag == 2) {
		std::cout << "East" << std::endl;
	}
	if (WinFlag == 0) {
		std::cout << "NA" << std::endl;
	}

	return 0;
}