#include "bits/stdc++.h"

using namespace std;
#pragma warning(disable:4996)

#define Seg_Max_N (1<<18) 

using Value = long long int;
const Value ini =0;
struct segtree {
	int N;
	vector<Value>dat;

	segtree() {}
	segtree(int n) :dat(2 * Seg_Max_N) {
		N = 1;
		while (N < n) N *= 2;
		for (int i = 0; i < 2 * N - 1; i++) {
			dat[i] = ini;
		}
	}
	Value connect(const Value&l, const Value&r) {
		return max(l,r);
	}
	// update k th element
	void update(int k, Value a) {
		k += N - 1;
		dat[k] = a;

		while (k > 0) {
			k = (k - 1) / 2;
			const Value al(dat[k * 2 + 1]);
			const Value ar(dat[k * 2 + 2]);
			dat[k] = connect(al, ar);
		}
	}
	// min [a, b)
	Value  query(int a, int b) { return query(a, b, 0, 0, N); }
	Value  query(int a, int b, int k, int l, int r) {
		if (r <= a or b <= l) return ini;
		if (a <= l and r <= b) return dat[k];
		const int m = (l + r) / 2;
		const Value al(query(a, b, k * 2 + 1, l, m));
		const Value ar(query(a, b, k * 2 + 2, m, r));
		return connect(al, ar);
	}
};

struct cake {
	int a;
	int b;
	long long int c;
};
bool operator<(const cake&l, const cake&r) {
	return l.a<r.a;
}
template<typename T> struct Compress {
	map<T, int>mp;
	map<int, T>revmp;

	Compress(vector<T>vs) {
		setmp(vs);
	}

	Compress() :mp(), revmp() {

	}
	void setmp(vector<T>vs) {
		sort(vs.begin(), vs.end());
		vs.erase(unique(vs.begin(), vs.end()), vs.end());
		for (int i = 0; i < static_cast<int>(vs.size()); ++i) {
			mp[vs[i]] = i;
			revmp[i] = vs[i];
		}
	}

};

int main() {
	int N;cin>>N;
	map<int,vector<cake>>mp;
	vector<int>bs{ 0 };
	for (int i = 0; i < N; ++i) {
		int a,b;
		long long int c;
		scanf("%d %d %lld",&a,&b,&c);
		bs.push_back(b);
		mp[a].push_back(cake{ a,b,c });
	}
	Compress<int> cb(bs);
	segtree seg(N+1);
	seg.update(0,0);
	for (auto m : mp) {
		vector<long long int>nums;
		for (auto c : m.second) {
			long long int num = seg.query(0, cb.mp[c.b]);
			nums.push_back(num);
		}

		int id = 0;
		for (auto c : m.second) {
			seg.update(cb.mp[c.b], max(seg.query(cb.mp[c.b], cb.mp[c.b] + 1), nums[id] + c.c));
			id++;
		}
	}
	long long int answer=seg.query(0,N+1);
	cout<<answer<<endl;
	return 0;
	
}