import itertools
N = int(input())
A = []
for n in range(N):
	X,Y,Z = map(int,input().split())
	V = X*Y*Z
	A.append([X,Y,Z,V])
A.sort(key = lambda x: - x[3])
B = [[float("inf") for i in range(3)] + [0]]
for a in A:
	for b in B:
		P = 0
		bx,by,bz = b[:-1]
		ax,ay,az = a[:-1]
		Ap = list(itertools.permutations([ax,ay,az],3))
		for p in Ap:
			if p[0] < bx and p[1] < by and p[2] < bz:
				 P = 1
				 break
		if P == 1:
			B.append(a[:-1] + [b[3] + 1])
			B.sort(key = lambda x: - x[3])
			break
print(B[0][3])