#include <bits/stdc++.h>

using namespace std;

using ll = long long;

constexpr ll INF = 1e17;

int main() {
    cin.tie(nullptr);
    ios::sync_with_stdio(false);
    int n, V, L;
    cin >> n >> V >> L;

    vector< vector<ll> > dp(n + 1, vector<ll>(V + 1, INF));
    dp[0][V] = 0;
    int prvx = 0;
    for (int i = 0; i < n; ++i) {
        int x, v;
        ll w;
        cin >> x >> v >> w;
        
        int hoge = x - prvx;
        for (int j = hoge; j <= V; ++j) {
            dp[i + 1][j - hoge] = min(dp[i + 1][j - hoge], dp[i][j]);
            ll& tar = dp[i + 1][min(j - hoge + v, V)]; 
            tar = min(tar, dp[i][j] + w);
        }
        prvx = x;
    }

    ll foo = L - prvx;
    ll ans = INF;
    for (ll i = foo; i <= V; ++i) {
        ans = min(ans, dp[n][i]);
    }
    cout << (ans >= INF ? -1 : ans) << "\n";
    return 0;
}