#include <bits/stdc++.h>
using namespace std;
int n;
const int N = 5e4 + 100, M = N * 4;
int h[N], e[M], ne[M], w[M], idx;
int dist[N];
bool st[N];

void add(int a, int b, int c)
{
    e[idx] = b, w[idx] = c, ne[idx] = h[a], h[a] = idx ++;
}

void spfa()
{
    int q[N], hh = 0, tt = 0;
    memset(dist, -0x3f, sizeof dist);
    q[tt ++] = 0;
    dist[0] = 0;
    st[0] = true;

    while (hh != tt)
    {
        int t = q[hh ++];
        if (hh == N) hh = 0;
        st[t] = false;
        for (int i = h[t]; ~i; i = ne[i])
        {
            int j = e[i];
            if (dist[j] < dist[t] + w[i])
            {
                dist[j] = dist[t] + w[i];
                if (!st[j])
                {
                    q[tt ++] = j;
                    if (tt == N) tt = 0;
                    st[j] = true;
                }
            }
        }
    }
}

int main(void)
{
    cin >> n;
    memset(h, -1, sizeof h);
    for (int i = 1; i <= 50001;  i ++)
    {
        add(i - 1, i, 0);
        add(i, i - 1, -1);
    }

    while (n --)
    {
        int a, b, c;
        cin >> a >> b >> c;
        a ++, b ++;
        add(a - 1, b , c);
    }

    spfa();
    cout << dist[50001] << endl;
    return 0;
}