Chef has $N$ axis-parallel rectangles in a 2D Cartesian coordinate system. These rectangles may intersect, but it is guaranteed that all their $4N$ vertices are pairwise distinct.
Unfortunately, Chef lost one vertex, and up until now, none of his fixes have worked (although putting an image of a point on a milk carton might not have been the greatest idea after all…). Therefore, he gave you the task of finding it! You are given the remaining $4N-1$ points and you should find the missing one.

-----Input-----
- The first line of the input contains a single integer $T$ denoting the number of test cases. The description of $T$ test cases follows.
- The first line of each test case contains a single integer $N$.
- Then, $4N-1$ lines follow. Each of these lines contains two space-separated integers $x$ and $y$ denoting a vertex $(x, y)$ of some rectangle.

-----Output-----
For each test case, print a single line containing two space-separated integers $X$ and $Y$ ― the coordinates of the missing point. It can be proved that the missing point can be determined uniquely.

-----Constraints-----
- $T \le 100$
- $1 \le N \le 2 \cdot 10^5$
- $|x|, |y| \le 10^9$
- the sum of $N$ over all test cases does not exceed $2 \cdot 10^5$

-----Subtasks-----
Subtask #1 (20 points):
- $T = 5$
- $N \le 20$
Subtask #2 (30 points): $|x|, |y| \le 10^5$
Subtask #3 (50 points): original constraints

-----Example Input-----
1
2
1 1
1 2
4 6
2 1
9 6
9 3
4 3

-----Example Output-----
2 2

-----Explanation-----
The original set of points are:

Upon adding the missing point $(2, 2)$, $N = 2$ rectangles can be formed:

```python

USER_FILENAME = "<user_code>"
import sys, json, builtins
import math, heapq, bisect, itertools, functools, collections, statistics, fractions, decimal, operator, array, random, re, string, os, pathlib
try:
    import resource as _res
except Exception:
    _res = None
from collections import Counter, defaultdict, deque, OrderedDict
from functools import lru_cache, reduce
from itertools import accumulate, permutations, combinations, product
from math import gcd, ceil, floor, sqrt
from decimal import Decimal
try:
    from typing import *
except Exception:
    pass
try:
    sys.setrecursionlimit(1_000_000)
except Exception:
    pass
try:
    import site as _site
    try:
        _sys_sites = _site.getsitepackages() if hasattr(_site, "getsitepackages") else []
        for _p in _sys_sites:
            if _p and _p not in sys.path:
                sys.path.append(_p)
    except Exception:
        pass
    try:
        _usp = _site.getusersitepackages()
        if isinstance(_usp, str):
            _usp = [_usp]
        for _p in _usp:
            if _p and _p not in sys.path:
                sys.path.append(_p)
    except Exception:
        pass
except Exception:
    pass

ns = {"__name__": "__main__"}
for _k, _v in list(globals().items()):
    if not _k.startswith("_"):
        ns[_k] = _v
_CODE = "test_case = int(input())\nwhile test_case :\n n = int(input())\n xdict = {}\n ydict = {}\n total_points = 4*n-1\n for _ in range(total_points) :\n  x,y = map(int, input().split())\n  if x not in xdict :\n   xdict[x] = 1 \n  else:\n   xdict[x] += 1 \n  \n  if y not in ydict :\n   ydict[y] = 1 \n  else:\n   ydict[y] += 1 \n \n for key in xdict.keys() :\n  if xdict[key] == 1 :\n   print(key, end = ' ')\n   break\n for key in ydict.keys():\n  if ydict[key] == 1 :\n   print(key)\n   break\n \n test_case -= 1\n \n \n \n \n \n \n \n \n \n \n "
_co = compile(_CODE, USER_FILENAME, "exec")
exec(_co, ns, ns)

```

Measured memory_bytes: 13255