#include <bits/stdc++.h>
using namespace std;
struct segment_tree{
  int N;
  vector<long long> ST;
  segment_tree(int N2){
    N = 1;
    while (N < N2){
      N *= 2;
    }
    ST = vector<long long>(N * 2 - 1, 0);
  }
  long long operator [](int i){
    return ST[N - 1 + i];
  }
  void update(int i, long long x){
    i += N - 1;
    ST[i] = x;
    while (i > 0){
      i = (i - 1) / 2;
      ST[i] = max(ST[i * 2 + 1], ST[i * 2 + 2]);
    }
  }
  long long range_max(int L, int R, int i, int l, int r){
    if (r <= L || R <= l){
      return 0;
    } else if (L <= l && r <= R){
      return ST[i];
    } else {
      int m = (l + r) / 2;
      return max(range_max(L, R, i * 2 + 1, l, m), range_max(L, R, i * 2 + 2, m, r));
    }
  }
  long long range_max(int L, int R){
    return range_max(L, R, 0, 0, N);
  }
};
int main(){
  int N;
  cin >> N;
  vector<int> A(N), B(N), C(N);
  for (int i = 0; i < N; i++){
    cin >> A[i] >> B[i] >> C[i];
  }
  vector<int> A2 = A;
  sort(A2.begin(), A2.end());
  A2.erase(unique(A2.begin(), A2.end()), A2.end());
  for (int i = 0; i < N; i++){
    A[i] = lower_bound(A2.begin(), A2.end(), A[i]) - A2.begin();
  }
  vector<int> B2 = B;
  sort(B2.begin(), B2.end());
  B2.erase(unique(B2.begin(), B2.end()), B2.end());
  for (int i = 0; i < N; i++){
    B[i] = lower_bound(B2.begin(), B2.end(), B[i]) - B2.begin();
  }
  int cnt1 = A2.size();
  int cnt2 = B2.size();
  vector<vector<pair<int, int>>> Q(cnt2);
  for (int i = 0; i < N; i++){
    Q[B[i]].push_back(make_pair(A[i], C[i]));
  }
  segment_tree ST(cnt1);
  for (int i = 0; i < cnt2; i++){
    int cnt = Q[i].size();
    sort(Q[i].begin(), Q[i].end(), greater<pair<int, int>>());
    for (int j = 0; j < cnt; j++){
      ST.update(Q[i][j].first, max(ST[Q[i][j].first], ST.range_max(0, Q[i][j].first) + Q[i][j].second));
    }
  }
  cout << ST.range_max(0, cnt1) << endl;
}