#include <bits/stdc++.h>
using namespace std;
using lint     = long long;
const lint inf = 1LL << 60;
const lint mod = 1000000007;

template <class T>
bool chmax(T &a, const T &b) {
    return (a < b) ? (a = b, 1) : 0;
}
template <class T>
bool chmin(T &a, const T &b) {
    return (b < a) ? (a = b, 1) : 0;
}

int main() {
    cin.tie(nullptr);
    ios::sync_with_stdio(false);
    lint n, V, L;
    cin >> n >> V >> L;
    vector<lint> x(n + 2), v(n + 2), w(n + 2);
    for (int i = 1; i <= n; ++i) {
        cin >> x[i] >> v[i] >> w[i];
    }
    x[n + 1] = L;
    v[n + 1] = 0;
    w[n + 1] = 0;
    vector<vector<lint>> dp(n + 2, (vector<lint>(V + 1, inf)));
    dp[0][V] = 0;
    for (int i = 1; i <= n + 1; ++i) {
        for (int j = 0; j <= V; ++j) {
            if (j + (x[i] - x[i - 1]) <= V)
                chmin(dp[i][j], dp[i - 1][j + (x[i] - x[i - 1])]);
        }
        for (int j = 0; j <= V; ++j) {
            chmin(dp[i][min(V, j + v[i])], dp[i][j] + w[i]);
        }
    }
    lint ret = inf;
    for (int j = 0; j <= V; ++j) {
        chmin(ret, dp[n + 1][j]);
    }
    if (ret == inf)
        cout << -1 << "\n";
    else
        cout << ret << "\n";
    return 0;
}