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| #include <iostream>
#include <cstdio>
#include <cstring>
#include <cmath>
#include <algorithm>
#include <vector>
#include <utility>
#include <set>
#include <map>
#ifdef XLor
#define dbg(args...) do {cout << #args << " -> "; err(args);} while (0)
#else
#define dbg(...)
#endif
void err() {std::cout << std::endl;}
template<typename T, typename...Args>
void err(T a, Args...args){std::cout << a << ' '; err(args...);}
#define ms(a,b) memset(a,b,sizeof(a))
using namespace std;
typedef long long ll;
typedef pair<int,int> PII;
typedef pair<ll,ll> PLL;
const int mod = 998244353;
const int inf = 1 << 30;
const int maxn = 100000 + 5;
const double eps = 1e-5;
const double pi = acos(-1.0);
int gcd(int a, int b) { return b ? gcd(b, a % b) : a; }
ll gcd(ll a, ll b) { return b ? gcd(b, a % b) : a; }
inline int dcmp(double x) {
// double大小比较，考虑精度eps
if (fabs(x) < eps) return 0;
else return x < 0 ? -1 : 1;
}
inline int zero(double x) {
return fabs(x) < eps;
}
struct Point {
int x, y;
Point(int x = 0, int y = 0): x(x), y(y){}
bool operator<(const Point& b) const {
return x < b.x;
}
bool operator==(const Point& b) const {
return x == b.x && y == b.y;
}
};
typedef Point Vector;
Vector operator + (Vector a, Vector b) { return Vector(a.x + b.x, a.y + b.y); }
Vector operator - (Point a, Point b) { return Vector(a.x - b.x, a.y - b.y); }
int cross(Vector a, Vector b) { return a.x * b.y - a.y * b.x; }
ll length(Vector a) { return 1ll * a.x * a.x + 1ll * a.y * a.y; }
int xmult(Point a, Point b, Point c) {
// 0 -> 三点共线
// + -> AC 在 AB 的逆时针方向
// - -> AC 在 AB 的顺时针方向
return cross(b - a, c - a);
}
struct Line {
Point p; Vector v;
Line(Point a, Point b) : p(a), v(b - a) {}
};
PLL getDistanceToLine(Point p, Point a, Point b) {
Vector v1 = b - a, v2 = p - a;
ll x = 1ll * cross(v1, v2) * cross(v1, v2);
ll y = length(v1);
if (x == 0) return { 0, 1 };
else if (x > 0) {
ll g = gcd(x, y);
return { x / g, y / g };
} else {
ll g = gcd(-x, y);
return { -x / g, y / g };
}
}
int n;
Point a[1005];
vector<Line> b, c;
int main() {
scanf("%d", &n);
for (int i = 1; i <= n; i++) scanf("%d%d", &a[i].x, &a[i].y);
for (int i = 1; i <= n; i++) {
for (int j = i + 1; j <= n; j++) {
b.push_back({a[i], a[j]});
}
}
map< PII, vector<PII> > mp;
for (auto& x: b) {
if (x.v.x == 0) {
mp[{0, 1}].push_back({x.p.x, x.p.y});
} else if (x.v.y == 0) {
mp[{1, 0}].push_back({x.p.x, x.p.y});
} else {
int g = gcd(abs(x.v.x), abs(x.v.y));
if (1ll * x.v.x * x.v.y > 0) {
mp[{abs(x.v.x) / g, abs(x.v.y) / g}].push_back({x.p.x, x.p.y});
} else {
mp[{-abs(x.v.x) / g, abs(x.v.y) / g}].push_back({x.p.x, x.p.y});
}
}
}
ll ans = 0; int sum = 0;
map<PII,int> cnt;
for (auto& v: mp) {
dbg(v.first.first, v.first.second);
// vector<PII> vec;
set<PLL> st;
PII ed = v.second[0];
Point a(v.second[0].first, v.second[0].second);
Point b(v.first.first, v.first.second);
b = a + b;
for (int i = 0; i < (int)v.second.size(); i++) {
Point p(v.second[i].first, v.second[i].second);
PLL h = getDistanceToLine(p, a, b);
if (xmult(p, a, b) < 0) h.first = -h.first;
dbg(h.first, h.second, xmult(p, a, b));
st.insert(h);
}
// dbg(st.size());
// set<ll> st;
// for (PII x: v.second) {
// st.insert(1ll * v.first.second * x.first - 1ll * v.first.first * x.second);
// }
sum += (int)st.size();
cnt[v.first] = (int)st.size();
dbg(st.size());
}
for (auto& x: cnt) {
ans += 1ll * x.second * (sum - x.second);
}
cout << ans / 2;
return 0;
}
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