#include<iostream>
#include<string>
#include<algorithm>
#include<cctype>
#include<set>
#include<bitset>
#include<math.h>
#include<map>
#include<queue>
#include<iomanip>
using namespace std;

int main(){
    int e = 0, w = 0;
    string s;
    cin >> s;
    for (int i = 0; i < s.size(); i++){
        if (s[i] == 'O'){
            e++;
            w = 0;
        }
        if (s[i] == 'X'){
            w++;
            e = 0;
        }
        if (e == 3){
            cout << "East" << endl;
            return 0;
        }
        if (w == 3){
            cout << "West" << endl;
            return 0;
        }
    }
    cout << "NA" << endl;
}