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:
test_case = int(input())
while test_case :
 n = int(input())
 xdict = {}
 ydict = {}
 total_points = 4*n-1
 for _ in range(total_points) :
  x,y = map(int, input().split())
  if x not in xdict :
   xdict[x] = 1 
  else:
   xdict[x] += 1 
  
  if y not in ydict :
   ydict[y] = 1 
  else:
   ydict[y] += 1 
 
 for key in xdict.keys() :
  if xdict[key] % 2 != 0 :
   print(key, end = ' ')
   break
 for key in ydict.keys():
  if ydict[key] % 2 != 0 :
   print(key)
   break
 
 test_case -= 1
 
 
 
 
 
 
 
 
 
 
 
test_case = int(input())
while test_case :
 n = int(input())
 xdict = {}
 ydict = {}
 total_points = 4*n-1
 for _ in range(total_points) :
  x,y = map(int, input().split())
  if x not in xdict :
   xdict[x] = 1 
  else:
   xdict[x] += 1 
  
  if y not in ydict :
   ydict[y] = 1 
  else:
   ydict[y] += 1 
 
 for key in xdict.keys() :
  if xdict[key] % 2 != 0 :
   print(key, end = ' ')
   break
 for key in ydict.keys():
  if ydict[key] % 2 != 0 :
   print(key)
   break
 
 test_case -= 1
 
 
 
 
 
 
 
 
 
 
 