#include<sstream>
#include<iostream>
#include<cstdio>
#include<cstdlib>
#include<cstring>
#include<cmath>
#include<string>
#include<vector>
#include<set>
#include<map>
#include<queue>
#include<numeric>
#include<functional>
#include<algorithm>
#include<bitset>
using namespace std;
#define rep(i,n) for(int i=0;i<(int)(n);i++)
#define all(v) v.begin(),v.end()
#define uniq(v) v.erase(unique(all(v)),v.end())
#define indexOf(v,x) (find(all(v),x)-v.begin())


#define INF 1e+10
#define EPS 1e-8
#define EQ(a,b) (abs(a-b)<EPS)

//誤差を考慮して足し算
double add(double a,double b){
	if(abs(a+b) < EPS*(abs(a)+abs(b)))return 0;
	return a+b;
}
struct P{//2次元ベクトル
	double x,y;
	P(){}
	P(double x,double y):x(x),y(y){}
	P operator + (P p){
		return P(add(x,p.x),add(y,p.y));
	}
	P operator - (P p){
		return P(add(x,-p.x),add(y,-p.y));
	}
	P operator * (double d){
		return P(x*d,y*d);
	}
	P operator / (double d){
		return P(x/d,y/d);
	}
	double dot(P p){//内積
		return add(x*p.x,y*p.y);
	}
	double det(P p){//外積
		return add(x*p.y,-y*p.x);
	}
	bool equal(P p){
		return (x-p.x)*(x-p.x)+(y-p.y)*(y-p.y) < EPS*EPS;
	}
	double norm()const{
		return sqrt(x*x+y*y);
	}
};



int main(){
	int n;
	P p[200];
	cin>>n;
	rep(i,n*2){
		cin>>p[i].x;
		cin>>p[i].y;
	}
	int ans=0;
	rep(i,n*2)rep(j,i){
		int cnt=0;
		rep(k,n){
			P q,r;
			double s,t;
			q=p[k*2];r=p[k*2+1];
			s=(p[i]-p[j]).det(p[i]-q);
			t=(p[i]-p[j]).det(p[i]-r);
			if(0<s+EPS&&t-EPS<0 || s-EPS<0&&0<t+EPS){
				cnt++;
			}
		}
		ans=max(ans,cnt);
	}
	cout<<ans<<endl;
	return 0;
}