#include <iostream>
#include <vector>
#include <map>
#include<string>
#include<queue>
#include<math.h>
#define all(x) begin(x),end(x)
#define ll long long
#define P pair<int,int>
#define lP pait<ll,ll>
using namespace std;
int main() {
    int e=0,w=0;
    string s;
    cin>>s;
    if(s.size()<3) cout<<"NA"<<endl;
    else{
    for(int i=0;i<s.size()-2;i++){
        if(s[i]=='O' and s[i+1]=='O' and s[i+2]=='O') {
            e++;
            if(e==1) break;
    }
        else if(s[i]=='X' and s[i+1]=='X' and s[i+2]=='X'){
            w++;
            if(w==1) break;
        }
    }
    }
    if(e==1) cout<<"East"<<endl;
    else if(w==1) cout<<"West"<<endl;
    else cout<<"NA"<<endl;
    return 0;
}