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

constexpr int N = 5100;

signed main() {
    int n, A, B;
    cin >> n >> A >> B;
    vector<array<int, 2>> a(n + 1), b(n + 1);
    for(int i = 1; i <= n; i++) {
        cin >> a[i][0] >> a[i][1] >> b[i][0] >> b[i][1];
        a[i][0] -= A, a[i][1] -= A, b[i][0] -= B, b[i][1] -= B;
    }
    vector<bitset<N>> f(n + 10), pre(n + 10);
    f[0].set(0);
    for(int i = 0; i < n + 10; i++) {
        if(i) pre[i] |= pre[i - 1];
        pre[i].set(i);
    }
    bitset<N> tmp;
    for(int i = 1; i <= n; i++) {
        a[i][0] = max(a[i][0], 0);
        a[i][1] = min(a[i][1], i);
        b[i][0] = max(b[i][0], 0);
        b[i][1] = min(b[i][1], i);
        if(a[i][0] > a[i][1] || b[i][0] > b[i][1]) continue;
        for(int j = a[i][1]; j >= a[i][0]; j--) {
            tmp = f[j] & (b[i][0] ? pre[b[i][1]] ^ pre[b[i][0] - 1] : pre[b[i][1]]);
            f[j + 1] |= tmp;
            f[j] |= tmp << 1;
        }
    }
    int ans = 0;
    for(int i = 0; i <= n; i++) {
        for(int j = 0; j <= n; j++) {
            if(f[i][j]) ans = max(ans, i + j);
        }
    }
    cout << ans << '\n';
    return 0;
}