#include <bits/stdc++.h>

using namespace std;

typedef long long ll;

set<pair<ll, ll>> spells;

ll gcd(ll a, ll b){
    if(b == 0){
        return a;
    }

    return gcd(b, a % b);
}

int main(){
    ios::sync_with_stdio(0);
    cin.tie(0);

    int n;
    cin >> n;

    vector<pair<ll, ll>> cities(n);

    for(int i = 0; i < n; ++i){
        ll x, y;

        cin >> x >> y;
        cities[i] = {x, y};

        for(int j = 0; j < i; ++j){
            ll dx = cities[j].first - cities[i].first;
            ll dy = cities[j].second - cities[i].second;

            if(dx == 0){
                spells.insert({0, 1});
                spells.insert({0,-1});
            } else if(dy == 0){
                spells.insert({1,0});
                spells.insert({-1, 0});
            } else{
                ll g = gcd(dx, dy);

                dx /= g;
                dy /= g;

                spells.insert({dx, dy});
                spells.insert({-1*dx, -1*dy});
            }
        }
    }

    cout << spells.size();

    cout << flush;

    return 0;
}