#include <iostream>
#include <cstdio>
#include<stdio.h>
#include<algorithm>
#include<cstring>
#include<math.h>
#include<memory>
#include<queue>
#include<vector>
using namespace std;
#define max_v 50010
#define INF 9999999
int tot;
int head[max_v];
int vis[max_v];
int dis[max_v];
int minn,maxx;
struct node
{
    int u,v,val;
    int next;
}Edge[max_v<<2];
void addEdge(int u,int v,int val)
{
    Edge[tot].u=u;
    Edge[tot].v=v;
    Edge[tot].val=val;
    Edge[tot].next=head[u];
    head[u]=tot++;
}
void spfa()
{
    for(int i=minn-1;i<=maxx;i++)
        dis[i]=-INF;
    queue<int> q;
    dis[maxx]=0;
    vis[maxx]=1;
    q.push(maxx);
    while(!q.empty())
    {
        int u=q.front();
        q.pop();
        vis[u]=0;
        for(int i=head[u];i!=-1;i=Edge[i].next)
        {
            int v=Edge[i].v;
            if(dis[v]<dis[u]+Edge[i].val)
            {
                dis[v]=dis[u]+Edge[i].val;
                if(!vis[v])
                {
                    vis[v]=1;
                    q.push(v);
                }
            }
        }
    }
    printf("%d\n",dis[minn-1]);
    return ;
}
int main()
{
    int n,a,b,c;
    while(~scanf("%d",&n))
    {
        tot=0;
        memset(head,-1,sizeof(head));
        memset(vis,0,sizeof(vis));
        maxx=0;
        minn=INF;
        for(int i=0;i<n;i++)
        {
            scanf("%d %d %d",&a,&b,&c);
            a++;
            b++;
            minn=min(minn,a);
            maxx=max(maxx,b);
            addEdge(b,a-1,c);
        }
        for(int i=minn;i<=maxx;i++)
        {
            addEdge(i,i-1,0);
            addEdge(i-1,i,-1);
        }
        spfa();
    }
    return 0;
}