#include <bits/extc++.h>
#include <atcoder/all>

using namespace std;
using ll = long long;
#define REP(i,n) for(int i=0;i<int(n);i++)
#define FOR(i,a,b) for(int i=a;i<=int(b);i++)
#define ALL(x) x.begin(),x.end()
#define INF INT_MAX
#define INFL LLONG_MAX / 4
using namespace atcoder;
using mint = modint998244353;
template<typename T> void chmin(T& a, T b) { a = min(a, b); }
template<typename T> void chmax(T& a, T b) { a = max(a, b); }
#define PR(x) cerr << #x << "=" << x << endl
using i128 = __int128_t;

int main() {
  int n;
  cin >> n;
  vector<ll> x(n), y(n);
  REP(i, n) cin >> x[i] >> y[i];

  int ans = 0;
  REP(i, n) {
    map<pair<ll, ll>, int> mp;
    bool ok = false;
    REP(j, n) {
      if(i == j) continue;
      ll dx = x[j] - x[i];
      ll dy = y[j] - y[i];
      if(dx == 0) dy = dy;
      if(dy == 0) dx = dx;
      ll g = gcd(abs(dx), abs(dy));
      dy /= g; dx /= g;
      mp[{dx,dy}] ++;
      if(mp[{dx,dy}] >= 2) ok =true;
    }
    if(ok) ans++;
  }
  cout << ans;
  return 0;
}