#include <iostream>
#include <vector>
#include <string>
#include <iomanip>
#include <queue>
#include <cmath>
#include <algorithm>
#include <tuple>
#include <iomanip>
#include <stdio.h>
#include <numeric>
#include <map>
#include <math.h>

#define int long long
#define double double
#define ull unsigned long long
#define all(a) a.begin(), a.end()
#define pii pair<int, int>
#define pb push_back

using namespace std;

pii correct(int x1, int y1, int x2, int y2, int x3, int y3) {
    if ((x2 - x1) * (x3 - x1) + (y2 - y1) * (y3 - y1) == 0) { // cos1 == 0 => 1 = 90 dg
        return {x2 + x3 - x1, y2 + y3 - y1};
    }
    if ((x1 - x2) * (x3 - x2) + (y1 - y2) * (y3 - y2) == 0) {
        return {x1 + x3 - x2, y1 + y3 - y2};
    }
    if ((x1 - x3) * (x2 - x3) + (y1 - y3) * (y2 - y3) == 0) {
        return {x1 + x2 - x3, y1 + y2 - y3};
    }
    return {101, 101};
}

bool square(int x1, int y1, int x2, int y2, int x3, int y3, int x4, int y4) {
    int one, two, three, four;
    one = (x1 - x2) * (x1 - x2) + (y1 - y2) * (y1 - y2);
    two = (x3 - x2) * (x3 - x2) + (y3 - y2) * (y3 - y2);
    three = (x4 - x3) * (x4 - x3) + (y4 - y3) * (y4 - y3);
    four = (x1 - x4) * (x1 - x4) + (y1 - y4) * (y1 - y4);
//    cout << one << " " << two << " " << three << " " << four << "\n";
    if (one == two and two == three and three == four and four == one) {
        return true;
    }
    return false;
}

map<pair<int, int>, int> m;

signed main()
{
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);
    int n;
    cin >> n;
    vector<pair<int, int>> a(n);
    for (int i = 0; i < n; i++) {
        cin >> a[i].first >> a[i].second;
        m[a[i]] = 1;
    }
    int ans = 0;
    for (int i = 0; i < n - 2; i++) {
        for (int j = i + 1 ; j < n - 1; j++) {
            for (int k = j + 1; k < n; k++) {
                pair<int, int> v = correct(a[i].first, a[i].second, a[j].first, a[j].second, a[k].first, a[k].second);
                if (m[v]) {
                    vector<pair<int, int>> q(4);
                    q[0] = a[i];
                    q[1] = a[j];
                    q[2] = a[k];
                    q[3] = v;
                    sort(all(q));
                    reverse(q.begin() + 2, q.end());
                    if (square(q[0].first, q[0].second, q[1].first, q[1].second, q[2].first, q[2].second, q[3].first, q[3].second)) {
                        ans++;
                    }
                }
            }
        }
    }
    cout << ans / 4;
}