#include <bits/stdc++.h>
#define FOR(i,bg,ed) for(ll i=(bg);i<(ed);i++)
#define REP(i,n) FOR(i,0,n)
#define MOD 1000000007
#define int long long
using namespace std;
typedef long long ll;
const int INF = 1e9;



signed main()
{
    string S;

    cin >> S;
    auto east = S.find("OOO");
    auto west = S.find("XXX");

    if (east == string::npos && west == string::npos) {
        cout << "NA" << endl;
    } else {
        if (east < west) {
            cout << "East" << endl;
        } else {
            cout << "West" << endl;
        }
    }
}