description: Monocarp is the coach of the Berland State University programming teams. He decided to compose a problemset for a training session for his teams.
  
  Monocarp has n problems that none of his students have seen yet. The i-th problem has a topic a_i (an integer from 1 to n) and a difficulty b_i (an integer from 1 to n). All problems are different, that is, there are no two tasks that have the same topic and difficulty at the same time.
  
  Monocarp decided to select exactly 3 problems from n problems for the problemset. The problems should satisfy at least one of two conditions (possibly, both):
  
    * the topics of all three selected problems are different; 
    * the difficulties of all three selected problems are different. 
  
  
  
  Your task is to determine the number of ways to select three problems for the problemset.
  
  Input
  
  The first line contains a single integer t (1 ≤ t ≤ 50000) — the number of testcases.
  
  The first line of each testcase contains an integer n (3 ≤ n ≤ 2 ⋅ 10^5) — the number of problems that Monocarp have.
  
  In the i-th of the following n lines, there are two integers a_i and b_i (1 ≤ a_i, b_i ≤ n) — the topic and the difficulty of the i-th problem.
  
  It is guaranteed that there are no two problems that have the same topic and difficulty at the same time.
  
  The sum of n over all testcases doesn't exceed 2 ⋅ 10^5.
  
  Output
  
  Print the number of ways to select three training problems that meet either of the requirements described in the statement.
  
  Example
  
  Input
  
  
  2
  4
  2 4
  3 4
  2 1
  1 3
  5
  1 5
  2 4
  3 3
  4 2
  5 1
  
  
  Output
  
  
  3
  10
  
  Note
  
  In the first example, you can take the following sets of three problems:
  
    * problems 1, 2, 4; 
    * problems 1, 3, 4; 
    * problems 2, 3, 4. 
  
  
  
  Thus, the number of ways is equal to three.
solution: import java.util.*;
  
  public class Solution{
      public static void main(String[] args){
          Scanner sc=new Scanner(System.in);
          int t=sc.nextInt();
          while(t-->0){
              int n=sc.nextInt();
              ArrayList<Integer>[] ar=new ArrayList[n+1];
              ArrayList<Integer>[] br=new ArrayList[n+1];
              for(int i=0;i<=n;i++){
                  ar[i]=new ArrayList<>();
                  br[i]=new ArrayList<>();
              }
              for(int i=0;i<n;i++){
                  int a=sc.nextInt();
                  int b=sc.nextInt();
                  ar[a].add(b);
                  br[b].add(a);
              }
              long ans=(1L*n*(n-1)*(n-2))/6;
              for(int i=1;i<=n;i++){
                  int size=ar[i].size()-1;
                  for(int a:ar[i]){
                      int s=br[a].size()-1;
                      ans-=1L*size*s;
                  }
              }
              System.out.println(ans);
          }
      }
  }