#include <bits/stdc++.h>
using namespace std;
constexpr int N = 1e6 + 10;
int n;
struct Node {
	int cnt, sum;
	Node(int c = 0, int s = 0) : cnt(c), sum(s) {}
	friend Node operator + (Node a, Node b) {return Node(a.cnt + b.cnt, a.sum ^ b.sum);}
	friend Node operator - (Node a, Node b) {return Node(a.cnt - b.cnt, a.sum ^ b.sum);}
	Node& operator += (Node x) {return *this = *this + x;}
	Node& operator -= (Node x) {return *this = *this - x;}
};
struct Bit {
	Node c[N];
	void upd(int p, Node x) {
		for(p; p < N; p += p & -p) c[p] += x;
	}
	Node qry(int p) {
		Node ans;
		for(; p; p -= p & -p) ans += c[p];
		return ans;
	}
}d1, d2, d3, d4;
struct Oper {
	int l, r, w;
	Oper(int _l, int _r, int _w) : l(_l), r(_r), w(_w) {}
};
vector<Oper> upd[N];
Node deg[N];
int main() {
	// freopen("in.txt", "r", stdin);
	ios::sync_with_stdio(false);
	cin.tie(0), cout.tie(0);
	cin >> n;
	for(int i = 1; i <= n; i ++) {
		int x1, x2, y1, y2;
		cin >> x1 >> y1 >> x2 >> y2;
		upd[x1].emplace_back(y1, y2, i);
		upd[x2].emplace_back(y1, y2, -i);
	}
	Node all(0, 0);
	auto get = [&] (int w){return Node(w > 0 ? 1 : -1, abs(w));};
	for(int i = 0; i < N; i ++) {
		for(auto [l, r, w] : upd[i]) {
			d1.upd(r, get(w));
			d2.upd(N - l - 1, get(w));
			all += get(w);
		}
		for(auto [l, r, w] : upd[i]) {
			if(w < 0) continue;
			Node cur = all - d1.qry(l) - d2.qry(N - r - 1) - get(w);
			deg[w] += cur;
		}
	}
	all = Node(0, 0);
	for(int i = N - 1; i >= 0; i --) {
		for(auto [l, r, w] : upd[i]) {
			if(w < 0) continue;
			Node cur = all - d3.qry(l) - d4.qry(N - r - 1);
			deg[w] += cur;
		}
		for(auto [l, r, w] : upd[i]) {
			if(w < 0) continue;
			d3.upd(r, get(w));
			d4.upd(N - l - 1, get(w));
			all += get(w);
		}
		for(auto [l, r, w] : upd[i]) {
			if(w > 0) continue;
			Node cur = all - d3.qry(l) - d4.qry(N - r - 1);
			deg[-w] -= cur;
		}
	}
	int ans = 0;
	for(int i = 1; i <= n; i ++) if(deg[i].cnt == 1) {
		int v = deg[i].sum;
		if(deg[v].cnt == 1) {
			assert(deg[v].sum == i);
			ans ++;
		}
	}
	cout << ans / 2 << '\n';
	return 0;
}