tioj 1205

using namespace std;
#include <vector>
#include <queue>
#include <algorithm>
#include <cmath>
#include <utility>
#include <bitset>
#include <set>
#include <string>
#include <stack>
#include <iomanip>
#include <map>

#define pb push_back
#define F first
#define S second
#define LL long long
#define mid (LB+RB)/2
#define iter(x) x.begin(),x.end()

/*
8e7 so dian
FHVirus so dian
youou so dian
KYW so dian
hubert so dian
jass so dian
tingyu so dian
*/

//IO
#include <iostream>
#define theyRSOOOOOOOOODIAN ios_base::sync_with_stdio(false),cin.tie(0);
#define endl '\n'

//workspace

#define pii pair<LL,LL>

inline LL cross (pii o,pii a,pii b){
    return (a.F - o.F) * (b.S - o.S) - (a.S - o.S) * (b.F - o.F);
}

inline LL dot (pii o,pii a,pii b){
    return (a.F - o.F) * (b.F - o.F) + (a.S - o.S) * (b.S - o.S);
}

pii vo;
inline bool cmp(pii a,pii b){
    if ((a.S - vo.S < 0) ^ (b.S - vo.S < 0))
        return a.S - vo.S >= 0;
    return cross(vo,a,b) <= 0;
}

inline void solve(int n){
    vector <pii> v;
    while (n--){
        int x,y;

        cin >> x >> y;
        v.pb({x,y});
    }
    vector <pii> sorted = v;

    int ans = 0;
    for (auto o:v){
        vo = o;
        sort (iter(sorted),cmp);
        vector <pair<pii,int>> it;
        bool exMinus = 0;
        if (sorted[0] != o)
            it.pb({sorted[0],1});
        else{
            it.pb({sorted[1],1});
            exMinus = 1;
        }

        for (int i=(sorted[0] != o ? 1 : 2);i<sorted.size();++i){
            if (sorted[i] == o){
                exMinus = 1;
                continue;
            }
            if ((sorted[i-1] != o && cross(o,sorted[i-1],sorted[i])) || (exMinus && cross(o,sorted[i-2],sorted[i])))
                it.pb({sorted[i],1});
            else
                ++it[it.size()-1].S;
            exMinus = 0;
        }

        for (int i=0,j=1;i<it.size();++i){
            //if (o.F == 0 && o.S == 1)
                //cout << it[i].F.F << ' ' << it[i].F.S << '\n';
            j = max(j,i+1);
            while (j+1 < i + it.size() && dot(o,it[i%it.size()].F,it[j%it.size()].F) > 0 && cross(o,it[i%it.size()].F,it[j%it.size()].F) < 0)
                ++j;

            if (!dot(o,it[i%it.size()].F,it[j%it.size()].F) && cross(o,it[i%it.size()].F,it[j%it.size()].F) < 0)
                ans += it[i%it.size()].S * it[j%it.size()].S;
        }
        //cout << o.F << ',' << o.S << ' ' << it.size() << ' ' << ans << '\n';
    }

    cout << ans << '\n';
}

int main(){
    theyRSOOOOOOOOODIAN
    int n;

    while (cin >> n && n) solve(n);

    return 0;
}