Count the number of possible triangles.cpp

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


// } Driver Code Ends
class Solution
{
    public:
    //Function to count the number of possible triangles.
    int findNumberOfTriangles(int nums[], int n)
    {
        // code here
        sort(nums,nums+n);
        int count=0;
        for(int i=n-1;i>=2;i--){
            int low=0;
            int high=i-1;
          while(low<=high){
            if(nums[low]+nums[high]>nums[i]){
              count+=(high-low);
              high--;
            }else{
                low++;
            }
          }  
        }
        
        return count;
    }
};


//{ Driver Code Starts.

int main()
{
    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.findNumberOfTriangles(arr,n) <<endl;
    }
    return 0;
}
// } Driver Code Ends