//３連勝
#include <iostream>
#include <cstdio>
using namespace std;

int east = 0, west = 0;

int main() {
    char input[100] = {};
    int i = 0;
    cin >>input;
    while (i<100) {
        if (input[i] == 'O') {west = 0; east++;}
        else if (input[i] == 'X') {west++; east = 0;}
        else if (input[i] == EOF) break;
        if (west == 3) {cout <<"West\n"; return 0;}
        else if (east == 3) {cout << "East\n"; return 0;}
        i++;
    }
    cout << "NA" << endl;
    return 0;
}