A convex polygon consisting of N vertices is given. The coordinates of each vertex are represented counterclockwise by (X1, Y1), (X2, Y2), ……, (XN, YN). No matter what straight line passes through the point P, find the coordinates of the point P so that the areas of the two convex polygons obtained after cutting are equal.

Constraints

* All inputs are integers

* 3 ≤ N ≤ 50

* 0 ≤ | Xi |, | Yi | ≤ 1000000

* The input polygon is a simple convex polygon.

* The output must satisfy max (| X-cX |, | Y-cY |) ≤ 0.0001 when the output coordinates are (X, Y) and the exact solution is (cX, cY).

Input

The input is given in the following format.

> N
> X1 Y1
> X2 Y2
> ……
> XN YN
>

Output

If there is a point that satisfies the condition of the problem statement, the coordinates of that point

> X Y
>

Output in the format of. If the point does not exist, output "NA" on one line.

Examples

Input

4
100 100
0 100
0 0
100 0


Output

50.00000 50.00000


Input

3
100 100
0 100
0 0


Output

NA
#include <bits/stdc++.h>
using namespace std;
const int dx[] = {1, 0, -1, 0};
const int dy[] = {0, -1, 0, 1};
const double EPS = 1e-9;
namespace std {
bool operator<(const complex<double> &lhs, const complex<double> &rhs) {
  if (real(lhs) == real(rhs)) {
    return imag(lhs) < imag(rhs);
  } else {
    return real(lhs) < real(rhs);
  }
}
}  // namespace std
double vector_length(complex<double> a) { return abs(a); }
double point_distance(complex<double> a, complex<double> b) {
  return abs(a - b);
}
complex<double> unit_vector(complex<double> a) { return a / abs(a); }
pair<complex<double>, complex<double> > normal_vector(complex<double> a) {
  complex<double> n1 = a * complex<double>(0, 1);
  complex<double> n2 = a * complex<double>(0, -1);
  return make_pair(n1, n2);
}
bool point_eq(complex<double> a, complex<double> b) { return abs(a - b) < EPS; }
double dot(complex<double> a, complex<double> b) { return real(conj(a) * b); }
double cross(complex<double> a, complex<double> b) { return imag(conj(a) * b); }
bool is_intersected_linesegment(pair<complex<double>, complex<double> > la,
                                pair<complex<double>, complex<double> > lb) {
  complex<double> a1 = la.first, a2 = la.second;
  complex<double> b1 = lb.first, b2 = lb.second;
  return (cross(a2 - a1, b1 - a1) * cross(a2 - a1, b2 - a1) < EPS) &&
         (cross(b2 - b1, a1 - b1) * cross(b2 - b1, a2 - b1) < EPS);
}
bool is_orthogonal(pair<complex<double>, complex<double> > a,
                   pair<complex<double>, complex<double> > b) {
  return dot(a.first - a.second, b.first - b.second) < EPS;
}
bool is_parallel(pair<complex<double>, complex<double> > a,
                 pair<complex<double>, complex<double> > b) {
  return cross(a.first - a.second, b.first - b.second) < EPS;
}
complex<double> intersection_point_linesegment(
    pair<complex<double>, complex<double> > la,
    pair<complex<double>, complex<double> > lb) {
  complex<double> a1 = la.first, a2 = la.second;
  complex<double> b1 = lb.first, b2 = lb.second;
  if (a1 == b1 or a1 == b2) return a1;
  if (a2 == b1 or a2 == b2) return a2;
  complex<double> b = b2 - b1;
  double d1 = abs(cross(b, a1 - b1));
  double d2 = abs(cross(b, a2 - b1));
  double t = d1 / (d1 + d2);
  return a1 + (a2 - a1) * t;
}
bool is_intersected_l(pair<complex<double>, complex<double> > la,
                      pair<complex<double>, complex<double> > lb) {
  return not is_parallel(la, lb);
}
complex<double> intersection_l(pair<complex<double>, complex<double> > la,
                               pair<complex<double>, complex<double> > lb) {
  complex<double> a1 = la.first, a2 = la.second;
  complex<double> b1 = lb.first, b2 = lb.second;
  complex<double> a = a2 - a1, b = b2 - b1;
  return a1 + a * cross(b, b1 - a1) / cross(b, a);
}
int ccw(complex<double> a, complex<double> b, complex<double> c) {
  b -= a;
  c -= a;
  if (cross(b, c) > 0) return +1;
  if (cross(b, c) < 0) return -1;
  if (dot(b, c) < 0) return +2;
  if (norm(b) < norm(c)) return -2;
  return 0;
}
double vertex_area(vector<complex<double> > v) {
  double ret = 0;
  for (int i = 0; i < v.size(); i++) {
    ret += cross(v[i], v[(i + 1) % v.size()]);
  }
  return ret / 2;
}
complex<double> find_opposite_point(vector<complex<double> > v,
                                    complex<double> p, int where_is_point) {
  double total_area = vertex_area(v);
  vector<complex<double> > alr;
  alr.push_back(p);
  for (int i = 1; i < v.size(); i++) {
    int one = (where_is_point + i) % v.size();
    int two = (where_is_point + i + 1) % v.size();
    alr.push_back(v[one]);
    complex<double> vec;
    vec = v[two] - v[one];
    complex<double> u = unit_vector(vec);
    double len = abs(vec);
    double upper = len;
    double lower = 0;
    for (int j = 0; j < 100; j++) {
      double mid = (upper + lower) / 2;
      complex<double> np = v[one] + u * mid;
      alr.push_back(np);
      if (vertex_area(alr) >= total_area / 2) {
        upper = mid;
      } else {
        lower = mid;
      }
      alr.pop_back();
    }
    complex<double> np = v[one] + u * upper;
    alr.push_back(np);
    if (abs(vertex_area(alr) - total_area / 2) < EPS) {
      return np;
    }
    alr.pop_back();
  }
  return complex<double>(-1, -1);
}
int main() {
  cout << fixed << setprecision(10);
  int N;
  cin >> N;
  vector<complex<double> > ver;
  for (int i = 0; i < N; i++) {
    int X, Y;
    cin >> X >> Y;
    ver.push_back(complex<double>(X, Y));
  }
  vector<pair<complex<double>, complex<double> > > chop;
  for (int i = 0; i < ver.size(); i++) {
    complex<double> p = ver[i] + (ver[(i + 1) % ver.size()] - ver[i]) /
                                     complex<double>(3.14, 0);
    complex<double> op = find_opposite_point(ver, p, i);
    chop.push_back(pair<complex<double>, complex<double> >(p, op));
  }
  complex<double> ret;
  int cnt = 0;
  for (int i = 0; i < chop.size(); i++) {
    for (int j = i + 1; j < chop.size(); j++) {
      if (is_intersected_linesegment(chop[i], chop[j])) {
        complex<double> p = intersection_point_linesegment(chop[i], chop[j]);
        if (cnt == 0) {
          ret = p;
          cnt = 1;
        } else {
          if (abs(p - ret) < EPS) cnt++;
        }
      }
    }
  }
  if (cnt == ver.size()) {
    cout << ret.real() << " " << ret.imag() << endl;
  } else {
    cout << "NA" << endl;
  }
  return 0;
}
