#include"bits/stdc++.h"
using namespace std;
#define REP(k,m,n) for(int (k)=(m);(k)<(n);(k)++)
#define rep(i,n) REP((i),0,(n))
using ll = long long;

template<typename T>
class SegmentTree {
private:
	using F = function<T(T, T)>; // モノイド型
	int n; // 横幅
	F f;   // モノイド
	T e;   // モノイド単位元
	vector<T> data;

public:
	// init忘れに注意
	SegmentTree() {}
	SegmentTree(F f, T e) :f(f), e(e) {}
	void init(int n_) {
		n = 1;
		while (n < n_)n <<= 1;
		data.assign(n << 1, e);
	}
	void build(const vector<T>& v) {
		int n_ = v.size();
		init(n_);
		rep(i, n_)data[n + i] = v[i];
		for (int i = n - 1; i >= 0; i--) {
			data[i] = f(data[(i << 1) | 0], data[(i << 1) | 1]);
		}
	}
	void set_val(int idx, T val) {
		idx += n;
		data[idx] = val;
		while (idx >>= 1) {
			data[idx] = f(data[(idx << 1) | 0], data[(idx << 1) | 1]);
		}
	}
	T query(int a, int b) {
		// [a,b)
		T vl = e, vr = e;
		for (int l = a + n, r = b + n; l < r; l >>= 1, r >>= 1) {
			if (l & 1)vl = f(vl, data[l++]); // unknown
			if (r & 1)vr = f(data[--r], vr); // unknown
		}
		return f(vl, vr);
	}
};

// if sort with A, this problem can reduce to LIS
// but for A_i==A_i+1's case,
// unite A's value and batch process
int main()
{
	// input
	int N;
	cin >> N;
	vector<vector<ll>> abc(N, vector<ll>(3));
	rep(i, N)rep(j, 3)cin >> abc[i][j];

	// preprocess
	map<ll, vector<pair<ll, ll>>> cakes;

	int cnt = 0;
	set<ll> st;
	map<ll, ll> trans;
	for (const auto& row : abc)st.insert(row[1]);
	for (const auto& num : st)trans[num] = cnt++;
	for (const auto& row : abc) {
		cakes[row[0]].push_back({ trans[row[1]], row[2] });
	}

	// segment tree init
	auto f = [](ll l, ll r) {return max(l, r); };
	SegmentTree<ll> seg(f, 0);
	seg.init(cnt);

	// query
	for (auto& itr : cakes) {
		vector<pair<ll, ll>> batch;
		for (auto& cake : itr.second) {
			ll b, c;
			tie(b, c) = cake;
			ll val = seg.query(0, b);
			ll bef = seg.query(b, b + 1);
			batch.push_back({ b, val + c });
		}
		for (auto& p : batch) {
			ll b, val;
			tie(b, val) = p;
			ll now = seg.query(b, b + 1);
			ll next = max(now, val);
			seg.set_val(b, next);
		}
	}
	cout << seg.query(0, cnt) << endl;
	return 0;
}