#include <iostream>
#include <map>
#include <set>
using namespace std;
set<pair<int,int> > s;
multimap<int,int> m;
int main()
{
    freopen("in.txt","r",stdin);
    int i,j,k,n,t=0,ans;
    multimap<int,int>::iterator p,q;
    for (scanf("%d",&t);t--;)
    {
        scanf("%d",&n);
        s.clear();
        m.clear();
        for (i=0;i<n;i++)
        {
            scanf("%d%d",&j,&k);
            m.insert(pair<int,int>(j,k));
            s.insert(pair<int,int>(j,k));
        }
        ans=0;
        for (p=m.begin();p!=m.end();p++)
            for (q=p,q++;q!=m.end();q++)
                if (q->first-p->first==q->second-p->second)
                {
                    if (s.find(pair<int,int>(p->first,q->second))!=s.end()&&s.find(pair<int,int>(q->first,p->second))!=s.end())
                    //if (m.find(pair<int,int>(p->first,q->second))!=m.end()&&m.find(pair<int,int>(q->first,p->second))!=m.end())
                        ans++;
                }
        printf("%d\n",ans);
    }
    return 0;
}