#include<iostream>
#include<set>
#include<utility>

using namespace std;

int N;
int x[50],y[50];

int main(){
  cin>>N;
  for(int i=0;i<N;i++){
    cin>>x[i]>>y[i];
  }
  set<pair<int,int> >s;
  for(int i=0;i+N/2<N;i++){
    s.insert(make_pair(x[i]+x[i+N/2],y[i]+y[i+N/2]));
  }
  if(N%2==1||s.size()>1){
    cout<<"NA"<<endl;
  }else{
    auto p=*begin(s);
    cout<<fixed<<p.first/2.<<' '<<p.second/2.<<endl;
  }
}

  