n = int(input())
xyz = [sorted(map(int,input().split()),reverse=1) for _ in range(n)]
xyz.sort(key=lambda x:x[-1])
dp = [0]*n
for i in range(n):
    c = 0
    xi,yi,zi = xyz[i]
    for j in range(i):
        xj,yj,zj = xyz[j]
        if xi > xj and yi > yj and zi > zj: c = max(c,dp[j])
    dp[i] = c+1
print(max(dp))