#include <iostream>
#include <string>
using namespace std;

int main(){
    string rus;
    cin >> rus;
    int flag = 0;
    for(int i = 0; i < (int)rus.size()-1 ; i++){
        if(rus[i] == 'O'){
            if(rus[i+1] == 'O'){
                if(rus[i+2] == 'O'){
                    cout << "East" << endl;
                    flag = 1;
                    break;
                }
            }
        }
        else if(rus[i] == 'X'){
            if(rus[i+1] == 'X'){
                if(rus[i+2] == 'X'){
                    cout << "West" << endl;
                    flag = 1;
                    break;
                }
            }
        }
    }
    if(flag) cout << "NA" << endl;
    return 0;
}