#include<iostream>
#include<algorithm>
#include<string>
using namespace std;
//typedef __int64 LL;
int main(){
    int ans=0;
    string s;
    cin>>s;
    if(s.size()>=2){
    for(int i=0;i<s.size()-2;i++){
        if(s[i]=='O' && s[i+1]=='O' && s[i+2]=='O'){
	   cout<<"East"<<endl;return 0;
	}   
	if(s[i]=='X' && s[i+1]=='X' && s[i+2]=='X'){
	   cout<<"West"<<endl;return 0;
	}   
    }
    }
    cout<<"NA"<<endl;
    return 0;
}