#include <cstdint>
#include <iostream>
#include <vector>
#include <map>
#include <set>
#include <algorithm>

using namespace std;

int N;
int B;
struct Point
{
	Point() {}
	Point(int x, int y, int p) : x(x), y(y), p(p) {}

	int x;
	int y;
	int p;
	int ix;
	int iy;
};
vector<Point> points;

void input(istream& in)
{
	in >> N >> B;
	points.resize(N);
	for (int i = 0; i < N; i++) {
		in >> points[i].x >> points[i].y >> points[i].p;
	}
}

int resolve()
{
	map<int, vector<Point*>> Xmap;
	map<int, vector<Point*>> Ymap;
	for (int i = 0; i < N; i++) {
		Point &pt = points[i];
		Xmap[pt.x].push_back(&pt);
		Ymap[pt.y].push_back(&pt);
	}
	
	vector<int> X;
	for (auto ite : Xmap) {
		X.push_back(ite.first);
	}
	map<int, int> X_to_index;
	int ix = 0;
	for (auto ite : X) {
		X_to_index[ite] = ix++;
	}

	vector<int> Y;
	for (auto ite : Ymap) {
		Y.push_back(ite.first);
	}
	map<int, int> Y_to_index;
	int iy = 0;
	for (auto ite : Y) {
		Y_to_index[ite] = iy++;
	}

	vector<vector<pair<int,int>>> sum_scores(Y.size());
	for (size_t iy = 0; iy < Y.size(); iy++) {
		sum_scores[iy].resize(X.size() + 1);
	}

	for (int i = 0; i < N; i++) {
		Point &pt = points[i];
		pt.ix = X_to_index[pt.x];
		pt.iy = Y_to_index[pt.y];

		auto& sum_score = sum_scores[pt.iy];
		for (size_t ix = pt.ix + 1; ix <= X.size(); ix++) {
			sum_score[ix].first++;
			sum_score[ix].second += pt.p;
		}
	}

	int best_count = 0;
	for (size_t ix1 = 0; ix1 < X.size(); ix1++) {
		for (size_t ix2 = ix1 + 1; ix2 <= X.size(); ix2++) {
			size_t iy1 = 0;
			size_t iy2 = 0;
			int score = 0;
			int count = 0;
			while (iy1 < Y.size()) {
				while (iy2 < Y.size() && score <= B) {
					if (count > best_count) {
						best_count = count;
					}
					count += sum_scores[iy2][ix2].first - sum_scores[iy2][ix1].first;
					score += sum_scores[iy2][ix2].second - sum_scores[iy2][ix1].second;
					iy2++;
				}
				if (score <= B) {
					if (count > best_count) {
						best_count = count;
					}
					break;
				}
				count -= sum_scores[iy1][ix2].first - sum_scores[iy1][ix1].first;
				score -= sum_scores[iy1][ix2].second - sum_scores[iy1][ix1].second;
				iy1++;
			}
		}
	}
	return best_count;
}

int main(int argc, char **argv)
{
	input(cin);
	cout << resolve() << endl;
	return 0;
}