#include <bits/stdc++.h>
using namespace std;

long long c[2010][2010];

int main() {
    cin.tie(nullptr);
    ios::sync_with_stdio(false);
    long long N, V, L; cin >> N >> V >> L;
    vector<long long> x(N), v(N), w(N);
    for (int i = 0; i < N; i++) cin >> x[i] >> v[i] >> w[i];
    x.emplace_back(L);
    memset(c, 1000000007, sizeof(c));
    long long inf = c[0][0];
    if (V < x[0]) {
        cout << -1 << "\n";
        return 0;
    }
    c[0][V-x[0]] = 0;
    for (int i = 0; i < N; i++) {
        for (int j = 0; j <= V; j++) {
            int d = x[i+1] - x[i];
            if (d <= j) {
                c[i+1][j-d] = min(c[i+1][j-d], c[i][j]);
            }
            int k = min(V, j+v[i]);
            if (d <= k) {
                c[i+1][k-d] = min(c[i+1][k-d], c[i][j]+w[i]);
            }
        }
    }
    long long ans = inf;
    for (int i = 0; i <= V; i++) {
        ans = min(ans, c[N][i]);
    }
    ans = ans == inf ? -1 : ans;
    cout << ans << "\n";
    return 0;
}