Count the triplets .cpp

// { Driver Code Starts
#include <bits/stdc++.h>
using namespace std;



 // } Driver Code Ends
//User function template for C++
class Solution{
public:	
	
	int countTriplet(int A[], int n)
	{
	    unordered_map<int,int> m ;
	    int count = 0;
	    for(int i = 0; i < n ; i ++ )
	    {
	        m[A[i]]++;
	    }
	   	for(int i = 0; i < n ; i ++ )
	    {
	        for(int j = i+1; j < n; j++)
	        {
	            
	            //cout<<A[i] +A[j] <<" ";
	            if( m.find(A[i] + A[j]) != m.end())
	            {
	                //cout<<A[i] + A[j]<<endl;
	                count++;
	            }
	        }
	        
	    }
	    return count;
	    
	}
};

// { Driver Code Starts.


int main() 
{
   	
   	ios_base::sync_with_stdio(0);
    cin.tie(NULL);
    cout.tie(NULL);
   
   	int t;
    cin >> t;
    while (t--)
    {
        int n;
        cin >> n;

        int arr[n];
        for(int i = 0; i < n; i++)
        	cin >> arr[i];

        Solution ob;
        cout << ob.countTriplet(arr, n) << "\n";

    }

    return 0;
}  // } Driver Code Ends