#include <bits/stdc++.h>
using namespace std;
using ll = long long;

const int maxN = 5050;
set<int> s[maxN];

int main() {
	cin.tie(0)->sync_with_stdio(0);
	int n, x, y;
	cin >> n >> x >> y;
	s[0].insert(0);
	for (int i = 0; i < n; i++) {
		int l, r, l1, r1;
		cin >> l >> r >> l1 >> r1;
		l -= x;
		r -= x;
		l1 -= y;
		r1 -= y;
		for (int j = i; j >= 0; j--) {
			if (r < j || l > j) continue;
			if (s[j].empty()) continue;
			auto it = s[j].upper_bound(r1);
			if (it != s[j].begin()) {
				it--;
				if (*it >= l1) {
					s[j+1].insert(*it);
					s[j].insert(*it + 1);
				}
			}
		}
	}
	int ans = 0;
	for (int i = 0; i <= n; i++) {
		if (!s[i].empty())
			ans = max(ans, i + *s[i].rbegin());
	}
	cout << ans << '\n';
	return 0;
}