#include #define rep(i, a) for (int i = 0; i < (a); i++) #define rep2(i, a, b) for (int i = (a); i < (b); i++) #define repr(i, a) for (int i = (a) - 1; i >= 0; i--) #define repr2(i, a, b) for (int i = (b) - 1; i >= (a); i--) using namespace std; typedef long long ll; const ll inf = 1e9; const ll mod = 1e9 + 7; typedef ll D; typedef complex P; const D eps = 0; D dot(P a, P b) { return real(conj(a) * b); } D cross(P a, P b) { return imag(conj(a) * b); } int ccw(P a, P b, P c) { b -= a; c -= a; if (cross(b, c) > eps) return 1; if (cross(b, c) < -eps) return -1; if (dot(b, c) < -eps) return 2; if (norm(b) < norm(c)) return -2; return 0; } bool intersectLS(P l1, P l2, P s1, P s2) { return ccw(l1, l2, s1) * ccw(l1, l2, s2) <= 0; } P ps[200]; int main() { int N; cin >> N; rep (i, N) { D x, y; cin >> x >> y; ps[i * 2] = P(x, y); cin >> x >> y; ps[i * 2 + 1] = P(x, y); } int ans = 0; rep (i, N * 2) rep (j, N * 2) { int cand = 0; rep (k, N) { if (intersectLS(ps[i], ps[j], ps[k * 2], ps[k * 2 + 1])) { cand++; } } ans = max(ans, cand); } cout << ans << endl; }