#include <bits/stdc++.h>

using namespace std;

#define EPS (1e-10)
#define equals(a, b) (fabs((a)-(b)) < EPS)

// ???/????????????
struct Point {
  double x, y;
  Point(double x = 0.0, double y = 0.0):x(x), y(y){}
  
  Point operator + (Point p) { return Point(x + p.x, y + p.y); }
  Point operator - (Point p) { return Point(x - p.x, y - p.y); }
  Point operator * (double a) { return Point(x * a, y * a); }
  Point operator / (double a) { return Point(x / a, y / a); }

  double abs() { return sqrt(norm()); }
  double norm() { return x*x + y*y; }

  bool operator < (const Point& p) const {
    return x != p.x ? x < p.x : y < p.y;
  }
  bool operator == (const Point& p) const {
    return fabs(x - p.x) < EPS && fabs(y - p.y) < EPS;
  }
};
typedef Point Vector;

// ??????/??´???
struct Segment {
  Point p1, p2;
  Segment(Point p1 = Point(), Point p2 = Point()):p1(p1), p2(p2){}
};
typedef Segment Line;

// ????????????????????????
double norm(Vector v)
{
  return v.x*v.x + v.y*v.y;
}
// ?????????????????§??????
double abs(Vector v)
{
  return sqrt(norm(v));
}
// ?????????????????????
double dot(Vector a, Vector b)
{
  return a.x*b.x + a.y*b.y;
}
// ??????????????????????????§??????
double cross(Vector a, Vector b)
{
  return a.x*b.y - a.y*b.x;
}
// ??´?????????
bool isOrthogonal(Vector a, Vector b)
{
  return equals(dot(a, b), 0.0);
}
bool isOrthogonal(Point a1, Point a2, Point b1, Point b2)
{
  return isOrthogonal(a1 - a2, b1 - b2);
}
bool isOrthogonal(Segment s1, Segment s2)
{
  return equals(dot(s1.p2 - s1.p1, s2.p2 - s2.p1), 0.0);
}
// ????????????
bool isParallel(Vector a, Vector b)
{
  return equals(cross(a, b), 0.0);
}
bool isParallel(Point a1, Point a2, Point b1, Point b2)
{
  return isParallel(a1 - a2, b1 - b2);
}
bool isParallel(Segment s1, Segment s2)
{
  return equals(cross(s1.p2 - s1.p1, s2.p2 - s2.p1), 0.0);
}
// ?°???±
Point project(Segment s, Point p)
{
  Vector base = s.p2 - s.p1;
  double r = dot(p - s.p1, base) / norm(base);
  return s.p1 + base * r;
}
// ????°?
Point reflect(Segment s, Point p)
{
  return p + (project(s, p) - p) * 2.0;
}
static const int COUNTER_CLOCKWISE = 1;
static const int CLOCKWISE         = -1;
static const int ONLINE_BACK       = 2;
static const int ONLINE_FRONT      = -2;
static const int ON_SEGMENT        = 0;
// ???????¨???????
int ccw(Point p0, Point p1, Point p2)
{
  Vector a = p1 - p0;
  Vector b = p2 - p0;
  if(cross(a, b) > EPS) return COUNTER_CLOCKWISE;
  if(cross(a, b) < -EPS) return CLOCKWISE;
  if(dot(a, b) < -EPS) return ONLINE_BACK;
  if(a.norm() < b.norm()) return ONLINE_FRONT;
  return ON_SEGMENT;
}
// ????????????
bool intersect(Point p1, Point p2, Point p3, Point p4)
{
  return (ccw(p1, p2, p3) * ccw(p1, p2, p4) <= 0 &&
	  ccw(p3, p4, p1) * ccw(p3, p4, p2) <= 0);
}
bool intersect(Segment s1, Segment s2)
{
  return intersect(s1.p1, s1.p2, s2.p1, s2.p2);
}
// ?????????????????¢
double getDistance(Point a, Point b)
{
  return abs(a - b);
}
// ??´?????¨?????¨????????¢
double getDistanceLP(Line l, Point p)
{
  return abs(cross(l.p2 - l.p1, p - l.p1) / abs(l.p2 - l.p1));
}
// ????????¨?????¨????????¢
double getDistanceSP(Segment s, Point p)
{
  if(dot(s.p2 - s.p1, p - s.p1) < 0.0) return abs(p - s.p1);
  if(dot(s.p1 - s.p2, p - s.p2) < 0.0) return abs(p - s.p2);
  return getDistanceLP(s, p);
}
// ????????????????????¢
double getDistance(Segment s1, Segment s2)
{
  if(intersect(s1, s2)) return 0.0;
  return min(min(getDistanceSP(s1, s2.p1), getDistanceSP(s1, s2.p2)),
	     min(getDistanceSP(s2, s1.p1), getDistanceSP(s2, s1.p2)));
}
// ???????????????
Point getCrossPoint(Segment s1, Segment s2)
{
  Vector base = s2.p2 - s2.p1;
  double d1 = abs(cross(base, s1.p1 - s2.p1));
  double d2 = abs(cross(base, s1.p2 - s2.p1));
  double t = d1 / (d1 + d2);
  return s1.p1 + (s1.p2 - s1.p1) * t;
}

int main()
{
  int N; cin >> N;
  vector<Point> p(N);
  for(int i = 0; i < N; i++) cin >> p[i].x >> p[i].y;

  if(p.size() % 1) {
    cout << "NA" << endl;
    return 0;
  }

  bool flag = true;
  for(int i = 0; i < N/2; i++) {
    Vector v1(p[i] - p[i+1]), v2(p[N/2+i] - p[(N/2+i+1)%N]);
    if(!isParallel(v1, v2) || v1.norm() != v2.norm()) flag = false;
  }

  if(flag) printf("%.10f %.10f\n", (p[0].x + p[N/2].x) / 2, (p[0].y + p[N/2].y) / 2);
  else cout << "NA" << endl;
  
  return 0;
}

Measured memory_bytes: 3272