#include "bits/stdc++.h"
using namespace std;
#define rep(i,n) for(int (i)=0;(i)<(int)(n);++(i))
#define rer(i,l,u) for(int (i)=(int)(l);(i)<=(int)(u);++(i))
#define reu(i,l,u) for(int (i)=(int)(l);(i)<(int)(u);++(i))
static const int INF = 0x3f3f3f3f; static const long long INFL = 0x3f3f3f3f3f3f3f3fLL;
typedef vector<int> vi; typedef pair<int, int> pii; typedef vector<pair<int, int> > vpii; typedef long long ll;
template<typename T, typename U> static void amin(T &x, U y) { if (y < x) x = y; }
template<typename T, typename U> static void amax(T &x, U y) { if (x < y) x = y; }

int main() {
	int N;
	while (~scanf("%d", &N)) {
		vector<array<int, 3>> v(N);
		rep(i, N) {
			array<int, 3> A;
			for (int i = 0; i < 3; ++ i)
				scanf("%d", &A[i]);
			sort(A.begin(), A.end());
			v[i] = A;
		}
		sort(v.begin(), v.end());
		vector<int> dp(N, 1);
		rep(i, N) {
			int x = dp[i];
			reu(j, i + 1, N) {
				auto a = v[i], b = v[j];
				if (a[0] < b[0] && a[1] < b[1] && a[2] < b[2])
					amax(dp[j], x + 1);
			}
		}
		int ans = *max_element(dp.begin(), dp.end());
		printf("%d\n", ans);
	}
	return 0;
}