D.D.1.

#include<bits/stdc++.h>
using namespace std;
#define int long long
#define uint unsigned long long
#define hayai ios_base::sync_with_stdio(false); cin.tie(0), cout.tie(0)
const int MAX = 2000005;
#define yes cout << "YES" <<"\n"
#define no cout << "NO" << "\n"
const long long mod=1e9+7;
int fb(vector<int> &ep ,int val)
{
  auto it = lower_bound(ep.begin(),ep.end(),val);
  if(it==ep.begin())
   return 0;
  else it--;
   return it-ep.begin()+1;

}
int32_t main() {
    hayai;
    int t =1;
    // cin >> t;

    while(t--)
    {
      int  n;
      cin >> n ;
      vector<pair<int,pair<int,int>>>v(n);
      for(int i =0;i<n;i++)
      {
        cin >> v[i].second.first >> v[i].first >> v[i].second.second ;
      }
      sort(v.begin(),v.end());
      int dp[n+1];
      dp[0]=0;
      vector<int> end;
      for(int i=0;i<n;i++)
       {
        end.push_back(v[i].first);
       }
       for(int i =0;i<n;i++)
       {
         int op1 = dp[i];
         int op2  = v[i].second.second;
         int j = fb(end,v[i].second.first);
         op2+=dp[j];
         dp[i+1]=max(op1,op2);
       }
       cout << dp[n] << "\n";
    }
}