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

int main(){
  string S;
  cin >> S;
  int w,e;
  string result;
  w = S.find("OOO");
  e = S.find("XXX");
  if(w == string::npos){
    if(e == string::npos)
      result = "NA";
    else
      result = "East";
  }
  else{
    if(e == string::npos)
      result = "West";
    else{
      if(w < e)
        result = "West";
      else
        result = "East";
    }
  }
  cout << result << "\n";
  return 0;
}