#include <iostream>
#include <vector>
#include <algorithm>
#include <set>
#include <map>

using namespace std;
using i64 = long long;
using u64 = unsigned long long;
#define rep(i,n) for(int i=0; i<(int)(n); i++)


struct Vec2{
    i64 x,y;
    Vec2 operator+(Vec2 r) const { return { x+r.x, y+r.y }; }
    Vec2 operator-() const { return { -x, -y }; }
    Vec2 operator-(Vec2 r) const { return { x-r.x, y-r.y }; }
    static i64 dot(Vec2 l, Vec2 r){ return l.x*r.x + l.y*r.y; }
    static i64 cross(Vec2 l, Vec2 r){ return l.x*r.y - l.y*r.x; }
    //      l
    //     ^
    //  +  |  -
    //   <-|->  r
};


struct ArgRange{
    Vec2 l = {0,0};
    Vec2 r = {0,0};
};


int N;
vector<Vec2> X;
vector<pair<u64, ArgRange>> argranges;


void enum_argranges(){
    map<u64, ArgRange> argranges_map;

    rep(a,N) rep(b,N) if(a != b){
        u64 mask = 0;
        rep(c,N){
            auto ab = X[b] - X[a];
            auto ac = X[c] - X[a];
            auto crossbc = Vec2::cross(ab, ac);
            auto dotbc = Vec2::dot(ab, ac);
            if(0 > crossbc) mask |= ((u64)1) << c;
            if(crossbc == 0 && 0 >= dotbc) mask |= ((u64)1) << c;
        }
        argranges_map[mask].r = X[b] - X[a];
    }

    rep(a,N) rep(b,N) if(a != b){
        u64 mask = 0;
        rep(c,N){
            auto ab = X[b] - X[a];
            auto ac = X[c] - X[a];
            auto crossbc = Vec2::cross(ab, ac);
            auto dotbc = Vec2::dot(ab, ac);
            if(0 < crossbc) mask |= ((u64)1) << c;
            if(crossbc == 0 && 0 >= dotbc) mask |= ((u64)1) << c;
        }
        argranges_map[mask].l = X[a] - X[b];
    }

    argranges.assign(argranges_map.begin(), argranges_map.end());
}


int main(){
    cin >> N;
    X.resize(N);
    rep(i,N) cin >> X[i].x >> X[i].y;
    rep(i,N) X[i] = X[i] + Vec2{ 1,1 };

    if(N == 1){ cout << "2\n"; return 0; }
    if(N == 2){ cout << "4\n"; return 0; }

    enum_argranges();
/*
    for(auto [mask, r] : argranges){
        for(int d=0; d<N; d++) cout << ((mask>>d) & 1);
        cout << " : ";
        cout << "( ( " << r.l.x << ", " << r.l.y << " ) , "
             << "( " << r.r.x << ", " << r.r.y << " ) )" << endl;
    }
*/
    set<u64> ans;
    ans.insert((((u64)1) << N) - 1);
    for(auto a : argranges) ans.insert(a.first);
    for(auto a : argranges) for(auto b : argranges) ans.insert(a.first & b.first);

    int argn = argranges.size();
    vector<int> overrange(argn, 0);
    rep(a,argn) if(Vec2::cross(argranges[a].second.l, argranges[a].second.r) < 0) overrange[a] |= 1;

    auto cancont = [](ArgRange a, ArgRange b) -> bool {
        if(Vec2::cross(a.l, b.l) > 0) return true;
        if(Vec2::cross(a.r, b.l) > 0) return true;
        if(Vec2::cross(a.l, b.r) > 0) return true;
        if(Vec2::cross(a.r, b.r) > 0) return true;
        return false;
    };

    rep(a,argn) rep(b,argn) rep(c,argn){
        auto A = argranges[a].second;
        auto B = argranges[b].second;
        auto C = argranges[c].second;
        if(!overrange[a] && !overrange[b] && !cancont(A, B)) continue;
        if(!overrange[b] && !overrange[c] && !cancont(B, C)) continue;
        if(!overrange[c] && !overrange[a] && !cancont(C, A)) continue;
        ans.insert(argranges[a].first & argranges[b].first & argranges[c].first);
    }

    cout << ans.size() << '\n';
    return 0;
}