/* -*- coding: utf-8 -*-
 *
 * 486.cc: No.486 3 Straight Win(3連勝) - yukicoder
 */

#include<cstdio>
#include<cstdlib>
#include<cstring>
#include<cmath>
#include<iostream>
#include<string>
#include<vector>
#include<map>
#include<set>
#include<stack>
#include<list>
#include<queue>
#include<deque>
#include<algorithm>
#include<numeric>
#include<utility>
#include<complex>
#include<functional>
 
using namespace std;

/* constant */

/* typedef */

/* global variables */

/* subroutines */

/* main */

int main() {
  string s;
  cin >> s;
  int n = s.size();

  int on = 0, xn = 0;
  for (int i = 0; i < n; i++) {
    if (s[i] == 'O') {
      xn = 0;
      if (++on >= 3) {
	puts("East");
	return 0;
      }
    }
    else {
      on = 0;
      if (++xn >= 3) {
	puts("West");
	return 0;
      }
    }
  }

  puts("NA");
  return 0;
}