#include <bits/stdc++.h>
using namespace std;

#define SZ(a) (int)a.size()
#define ALL(a) a.begin(), a.end()
#define FOR(i, a, b) for (int i = (a); i<(b); ++i)
#define RFOR(i, b, a) for (int i = (b)-1; i>=(a); --i)
#define MP make_pair
#define PB push_back
#define F first
#define S second
#define FILL(a, b) memset(a, b, sizeof(a))

typedef long long LL;
typedef pair<int, int> PII;
typedef vector<int> VI;

const int MAX = 307;

struct Point {
	int x, y;
	Point() {}
	Point(int _x, int _y): x(_x), y(_y) {}
	Point operator-(const Point& p) const {
		return {x - p.x, y - p.y};
	}
	LL operator*(const Point& p) const {
		return (LL)x * p.y - (LL)p.x * y;
	}
	int hp() const {
		return y < 0 || (y == 0 && x < 0);
	}
} p[MAX];

bool cmpPolar(const Point& p1, const Point& p2) {
	if (p1.hp() != p2.hp()) {
		return p1.hp() < p2.hp();
	}
	return p1 * p2 > 0;
}

vector<int> idxes[MAX], invIdxes[MAX];
vector<int> vec[MAX][MAX];

int main()
{
	ios::sync_with_stdio(false);
	cin.tie(0);
	int n;
	cin >> n;
	FOR(i, 0, n) {
		cin >> p[i].x >> p[i].y;
		FOR(j, 0, n) {
			if (j != i) {
				idxes[i].push_back(j);
			}
		}
	}
	FOR(i, 0, n) {
		sort(ALL(idxes[i]), [&](int j1, int j2) {return cmpPolar(p[j1] - p[i], p[j2] - p[i]);});
		invIdxes[i].resize(n, -1);
		FOR(j, 0, n - 1) {
			invIdxes[i][idxes[i][j]] = j;
		}
	}
	FOR(i, 0, n) {
		FOR(j, 0, n) {
			if (i == j) {
				continue;
			}
			for (int k = invIdxes[i][j] + 1; ; k++) {
				if (k == n - 1) {
					k = 0;
				}
				int l = idxes[i][k];
				if ((p[j] - p[i]) * (p[l] - p[i]) <= 0) {
					break;
				}
				if (vec[i][j].empty() || (p[vec[i][j].back()] - p[j]) * (p[l] - p[j]) > 0) {
					vec[i][j].push_back(l);
				}
			}
		}
	}
	LL nonConvex = 0;
	FOR(i, 0, n) {
		FOR(j, 0, n) {
			if (i == j) {
				continue;
			}
			int ptr = 0;
			for (int k : vec[i][j]) {
				while (ptr < SZ(vec[j][i]) && (p[k] - p[i]) * (p[vec[j][i][ptr]] - p[i]) > 0) {
					ptr++;
				}
				nonConvex += ptr;
			}
		}
	}
	LL s = 0;
	FOR(i, 0, n) {
		FOR(j, 0, i) {
			s += (LL)SZ(vec[i][j]) * SZ(vec[j][i]);
		}
	}
	cout << (s + nonConvex) / 2 << "\n";
	return 0;
}