#include <algorithm>
#include <bitset>
#include <cassert>
#include <cctype>
#include <cmath>
#include <complex>
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <ctime>
#include <iostream>
#include <map>
#include <queue>
#include <set>
#include <string>
#include <utility>
#include <vector>
using namespace std;

#define fi first
#define se second
#define pb push_back
#define all(x) (x).begin(), (x).end()
#define sz(x) (int((x).size()))
#define bit(x) (1 << (x))
#define cnt1(x) (__builtin_popcount(x))

template<class T>
inline void chkmax(T& x, T y) {
    if (x < y) x = y;
}

template<class T>
inline void chkmin(T& x, T y) {
    if (y < x) x = y;
}

typedef long long LL;
typedef double DB;
typedef pair<int, int> PII;
typedef vector<int> VI;
struct PT {
    int x, y;
};

inline int sqr(int x) {
    return x * x;
}

int dis2(PT& p1, PT& p2) {
    return sqr(p1.x - p2.x) + sqr(p1.y - p2.y);
}

const int MX = 25;
int n;
PT p[MX], q[5];
int chk[MX];
int rlt;

void calc(int k) {
    int i, dd;
    
    if (k == 4) {
        dd = dis2(q[3], q[0]);
        if (!dd) return;
        for (i = 0; i < 3; i++) {
            if (dis2(q[i], q[i + 1]) != dd) return;
        }
        if (dis2(q[0], q[2]) != dis2(q[1], q[3])) return;
        rlt++;
        return;
    }
    for (i = 0; i < n; i++) {
        if (chk[i]) continue;
        chk[i]++;
        q[k] = p[i];
        calc(k + 1);
        chk[i]--;
    }
}

int main() {
    
    int i;
    
    while (scanf("%d", &n) == 1) {
        for (i = 0; i < n; i++) scanf("%d%d", &p[i].x, &p[i].y);
        rlt = 0;
        calc(0);
        rlt /= 8;
        printf("%d\n", rlt);
    }
    return 0;
}