#include <iostream>

using namespace std;

const int MAXN = 2000;

int n, s[MAXN + 1], p[MAXN], e[MAXN], a[MAXN];

// DP[i][j] = maximum free time available up to s_i when having studied for (j <= i) of exam 0, 1, ..., (i-1).
int DP[MAXN + 1][MAXN + 1];

int main()
{
	cin >> n;
	for (int i = 0; i < n; i++)
		cin >> s[i] >> p[i] >> e[i] >> a[i];
	s[n] = 1000000000; // 1e9

	DP[0][0] = s[0];
	for (int exam_id = 0; exam_id < n; exam_id++) {
		// Initialization of the next layer:
		for (int studied = 0; studied <= exam_id + 1; studied++)
			DP[exam_id + 1][studied] = -1;

		for (int studied = 0; studied <= exam_id; studied++) {
			if (DP[exam_id][studied] < 0) continue;

			// Now, we can study for exam exam_id if time_left >= a[i].
			if (DP[exam_id][studied] >= a[exam_id]) {
				DP[exam_id + 1][studied + 1] = max(
					DP[exam_id + 1][studied + 1],
					(DP[exam_id][studied] - a[exam_id]) + (s[exam_id + 1] - p[exam_id])
				);
			}

			// We can also not study for exam exam_id.
			DP[exam_id + 1][studied] = max(
				DP[exam_id + 1][studied],
				(DP[exam_id][studied]) + (s[exam_id + 1] - e[exam_id])
			);
		}
	}

#ifdef DEBUG
	for (int i = 0; i <= n; i++) {
		for (int j = 0; j <= i; j++)
			cout << DP[i][j] << " ";
		cout << endl;
	}
#endif

	int result = n;
	while (DP[n][result] < 0) result--;
	cout << result << endl;
	return 0;
}