#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef unsigned long long ull;
typedef vector<int> VI;
typedef vector<VI> VVI;
#define REP(i, n)           for(int(i)=0;(i)<(n);++(i))
#define FOR(i, f, t)        for(int(i)=(f);(i)<(t);(++i))
#define RREP(i, n)          for(int(i)=(n)-1;(i)>=0;--(i))
#define FOREACH(it, c)      for(auto it=(c).begin();it!=(c).end();++it)
const int MOD = int(1e9+7);

int res = 0;

int N, B;
int x[444],y[444],p[444];

int m1[444][444];
int m2[444][444];

int s1(int x1, int y1, int x2, int y2){
    int sum = m1[y2][x2];
    if(x1 > 0) sum -= m1[y2][x1-1];
    if(y1 > 0) sum -= m1[y1-1][x2];
    if(x1 > 0 && y1 > 0) sum += m1[y1-1][x1-1];
    return sum;
}
int s2(int x1, int y1, int x2, int y2){
    int sum = m2[y2][x2];
    if(x1 > 0) sum -= m2[y2][x1-1];
    if(y1 > 0) sum -= m2[y1-1][x2];
    if(x1 > 0 && y1 > 0) sum += m2[y1-1][x1-1];
    return sum;
}

int main(){
    do { cin.tie(0); ios_base::sync_with_stdio(false); } while(0);

    cin >> N >> B;

    map<int,int> mx, my;

    REP(i,N){
        cin >> x[i] >> y[i] >> p[i];
        mx[x[i]] = 1;
        my[y[i]] = 1;
    }

    int w = 0; FOREACH(it, mx) it->second = w++;
    int h = 0; FOREACH(it, my) it->second = h++;

    REP(i,N){
        int xx = mx[x[i]], yy = my[y[i]];
        m1[yy][xx] += p[i];
        m2[yy][xx] ++;
    }

    FOR(x,1,w){
        m1[0][x] = m1[0][x] + m1[0][x-1];
        m2[0][x] = m2[0][x] + m2[0][x-1];
    }
    FOR(y,1,h){
        m1[y][0] = m1[y][0] + m1[y-1][0];
        m2[y][0] = m2[y][0] + m2[y-1][0];
    }
    FOR(y,1,h) FOR(x,1,w){
        m1[y][x] = m1[y][x] + m1[y][x-1] + m1[y-1][x] - m1[y-1][x-1];
        m2[y][x] = m2[y][x] + m2[y][x-1] + m2[y-1][x] - m2[y-1][x-1];
    }

    int maxv = 0;
    REP(y1,h)REP(x1,w){
        int x2 = x1;
        for(int y2 = h-1; y2 >= y1; y2--){
            while(x2 < w){
                if(s1(x1,y1,x2,y2) > B) break;
                maxv = max(maxv, s2(x1,y1,x2,y2));
                x2++;
            }
        }
    }
    cout << maxv << endl;
    return 0;
}