#include <bits/stdc++.h>
#define MULTI int _; cin >> _; while (_--)
#define fi first
#define se second
#define pb(a) push_back(a)
#define rep(i, n) for (int i = 0; i < n; i++)
#define reps(i, n, m) for (int i = n; i <= m; i++)
#define repsv(i, n, m) for (int i = n; i >= m; i--)
#define vsz(a) (int)(a.size())
#define mp(a, b) make_pair(a, b)
#define all(a) a.begin(), a.end()

using namespace std;

typedef pair<double, double> pdd;
typedef pair<int, int> pii;
typedef vector<bool> vb;
typedef vector<int> vi;
typedef long long int ll;
typedef long double ld;
typedef vector<ll> vll;

#ifdef LOCAL
#include "debugs.hpp"
#else
#define dbg(...) 0
#endif

#define NO INT_MIN

void solve(){
    int n;
    int ib, tb;
    cin >> n >> ib >> tb;
    vi dp(5005, NO);
    dp[0] = 0;
    rep(_i, n){
        int i1, i2, t1, t2;
        cin >> i1 >> i2 >> t1 >> t2;
        i1 -= ib, i2 -= ib, t1 -= tb, t2 -= tb;
        repsv(j, n, 0){
            if(dp[j] != NO){
                if(i1 <= j && i2 >= j && dp[j] >= t1 && dp[j] <= t2){
                    dp[j+1] = max(dp[j+1], dp[j]);
                    dp[j]++;
                }
            }
        }
    }
    int res = 0;
    reps(j, 1, n)
        res = max(res, j + dp[j]);
    cout << res << '\n';
}

int main(){
    ios_base::sync_with_stdio(false); cin.tie(0);
    // MULTI
    solve();
}