#include <string>
#include <vector>
#include <algorithm>
#include <numeric>
#include <set>
#include <map>
#include <queue>
#include <iostream>
#include <sstream>
#include <cstdio>
#include <cmath>
#include <ctime>
#include <cstring>
#include <cctype>
#include <cassert>
#include <limits>
#include <functional>
#define rep(i,n) for(int (i)=0;(i)<(int)(n);++(i))
#define rer(i,l,u) for(int (i)=(int)(l);(i)<=(int)(u);++(i))
#define reu(i,l,u) for(int (i)=(int)(l);(i)<(int)(u);++(i))
#if defined(_MSC_VER) || __cplusplus > 199711L
#define aut(r,v) auto r = (v)
#else
#define aut(r,v) __typeof(v) r = (v)
#endif
#define each(it,o) for(aut(it, (o).begin()); it != (o).end(); ++ it)
#define all(o) (o).begin(), (o).end()
#define pb(x) push_back(x)
#define mp(x,y) make_pair((x),(y))
#define mset(m,v) memset(m,v,sizeof(m))
#define INF 0x3f3f3f3f
#define INFL 0x3f3f3f3f3f3f3f3fLL
using namespace std;
typedef vector<int> vi; typedef pair<int,int> pii; typedef vector<pair<int,int> > vpii; typedef long long ll;
template<typename T, typename U> inline void amin(T &x, U y) { if(y < x) x = y; }
template<typename T, typename U> inline void amax(T &x, U y) { if(x < y) x = y; }

int main() {
	int N, B;
	scanf("%d%d", &N, &B);
	vector<int> X(N), Y(N), P(N);
	rep(i, N)
		scanf("%d%d%d", &X[i], &Y[i], &P[i]);
	vi xs = X, ys = Y;
	sort(all(xs)); xs.erase(unique(all(xs)), xs.end());
	sort(all(ys)); ys.erase(unique(all(ys)), ys.end());
	int W = xs.size(), H = ys.size();
	vector<vi> cnt(H, vi(W, 0)), pt(H, vi(W, 0));
	rep(i, N) {
		int xi = lower_bound(all(xs), X[i]) - xs.begin();
		int yi = lower_bound(all(ys), Y[i]) - ys.begin();
		++ cnt[yi][xi];
		pt[yi][xi] += P[i];
	}
	int ans = 0;
	
	rep(top, H) {
		vi cntf(W, 0), ptf(W, 0);
		reu(bot, top, H) {
			rep(j, W) {
				cntf[j] += cnt[bot][j];
				ptf[j] += pt[bot][j];
			}
			int curpt = 0, curcnt = 0;
			for(int le = 0, ri = 0; le < W; ++ le) {
				for(; ri < W && curpt + ptf[ri] <= B; ++ ri) {
					curpt += ptf[ri];
					curcnt += cntf[ri];
				}
				amax(ans, curcnt);
				curpt -= ptf[le];
				curcnt -= cntf[le];
			}
		}
	}
	printf("%d\n", ans);
	return 0;
}