e158

/* e158           */
/* AC (61ms, 3MB) */
#include <cstdio>
#include <queue>
#include <vector>

using namespace std;

const int maxn = 50005 , INF = 1e9;

struct Edge{
    int to , w;
};

vector <Edge> g[maxn];
int cur = 0 , n , a , b , c , max0 = 0;
int d[maxn];
bool in[maxn];

int spfa(int s , int t) {
    queue <int> q;
    fill(in, in + max0 + 1, 0);
    fill(d, d + max0 + 1, INF);
    d[s] = 0; q.push(s);
    while(q.size()) {
        int now = q.front(); q.pop(); in[now] = 0;
        for(int i = 0, l = g[now].size(); i < l; ++i) {
            int nex = g[now][i].to;
            if(d[nex] == INF || d[nex] < d[now] + g[now][i].w) {
                d[nex] = d[now] + g[now][i].w;
                if(!in[nex]) in[nex] = 1 , q.push(nex);
            }
        }
    }
    return d[t];
}

int main() {
    scanf("%d", &n);
    for(int i = 1; i <= n; ++i) {
        scanf("%d %d %d", &a, &b, &c);
        g[a - 1].push_back({b, c});
        max0 = max(max0, b);
    }
    for(int i = 0; i < max0; ++i) g[i].push_back({i + 1, 0}), g[i + 1].push_back({i, -1});
    printf("%d\n",spfa(0, max0));

    return 0;
}