# coding: utf-8
N,B = map(int,raw_input().split())
xyp = [map(int,raw_input().split()) for i in xrange(N)]
xy = list(set((x1,y2) for x1,y1,p1 in xyp for x2,y2,p2 in xyp))
M = len(xy)
ans = 1
for i in xrange(M):
    x1,y1 = xy[i]
    for j in xrange(i+1,M):
        x2,y2 = xy[j]
        l,r,d,u = min(x1,x2),max(x1,x2),min(y1,y2),max(y1,y2)
        in_square = [p for x,y,p in xyp if r >= x >= l and u >= y >= d]
        if sum(in_square) <= B:
            ans = max(ans, len(in_square))
print ans