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

int main() {
    string s,ans = "NA\n";
    cin >> s;
    for(int i = 2;s[i];i++){
        if(s[i-2]== 'O'&&s[i-1]=='O'&&s[i]=='O'){
            ans="East\n";
            break;
        }
        else if(s[i-2]=='X'&&s[i-1]=='X'&&s[i]=='X'){
            ans="West\n";
            break;
        }
    }
    cout << ans;
return 0;
}