import std.stdio, std.array, std.string, std.conv, std.algorithm;
import std.typecons, std.range, std.random, std.math, std.container;
import std.numeric, std.bigint, core.bitop, core.stdc.stdio, std.bitmanip;


void main() {
    alias Tuple!(int, "x", int, "y", int, "p") Point;
    int N, B;
    Point[] p;

    scanf("%d %d", &N, &B);
    p = new Point[](N);
    foreach (i; 0..N) {
        int x, y, po;
        scanf("%d %d %d", &x, &y, &po);
        p[i] = Point(x, y, po);
    }

    p.sort!"a.x < b.x"();
    int prev = p[0].x;
    p[0].x = 0;
    foreach (i; 1..N) {
        int cur = p[i].x;
        p[i].x = (p[i].x == prev) ? p[i-1].x : p[i-1].x + 1;
        prev = cur;
    }
    
    p.sort!"a.y < b.y"();
    prev = p[0].y;
    p[0].y = 0;
    foreach (i; 1..N) {
        int cur = p[i].y;
        p[i].y = (p[i].y == prev) ? p[i-1].y : p[i-1].y + 1;
        prev = cur;
    }


    auto acm_score = new int[][](N+1, N+1);
    auto acm_exist = new int[][](N+1, N+1);

    foreach (i; 0..N) {
        acm_score[p[i].x+1][p[i].y+1] = p[i].p;
        acm_exist[p[i].x+1][p[i].y+1] = 1;
    }

    foreach (i; 0..N+1) {
        foreach (j; 0..N) {
            acm_score[i][j+1] += acm_score[i][j];
            acm_exist[i][j+1] += acm_exist[i][j];
        }
    }
    
    foreach (j; 0..N+1) {
        foreach (i; 0..N) {
            acm_score[i+1][j] += acm_score[i][j];
            acm_exist[i+1][j] += acm_exist[i][j];
        }
    }

    int hi = N*N+1;
    int lo = 0;
    while (hi - lo > 1) {
        int mid = (hi + lo) / 2;
        bool ok;
        a:foreach (h; 1..mid+1) {
            if (mid % h != 0) continue;
            int w = mid / h;
            foreach (i; 0..N-h+1) {
                foreach (j; 0..N-w+1) {
                    if (acm_score[i+h][j+w] -
                        acm_score[i+h][j] -
                        acm_score[i][j+w] +
                        acm_score[i][j] <= B) {
                        ok = true;
                        break a;
                    }
                }
            }
        }
        if (ok) lo = mid;
        else hi = mid;
    }

    int ans = 0;
    foreach (h; 1..lo+1) {
            if (lo % h != 0) continue;
            int w = lo / h;
            foreach (i; 0..N-h+1) {
                foreach (j; 0..N-w+1) {
                    if (acm_score[i+h][j+w] -
                        acm_score[i+h][j] -
                        acm_score[i][j+w] +
                        acm_score[i][j] <= B) {
                        ans = max(ans,
                                  acm_exist[i+h][j+w] -
                                  acm_exist[i+h][j] -
                                  acm_exist[i][j+w] +
                                  acm_exist[i][j]);
                    }
                }
            }
        }
    ans.writeln;
}