#include <bits/stdc++.h>
#define all(vec) vec.begin(), vec.end()
#define pb push_back
#define eb emplace_back
#define fi first
#define se second
using namespace std;
using ll = long long;
using P = pair<ll, ll>;
template <class T>
using V = vector<T>;
constexpr ll INF = (1LL << 60) - 1LL;
constexpr ll MOD = 998244353LL;
constexpr int dx[4] = {0, 1, 0, -1}, dy[4] = {1, 0, -1, 0};
template <class T>
void chmin(T &a, T b) { a = min(a, b); }
template <class T>
void chmax(T &a, T b) { a = max(a, b); }
void debug() { cerr << "ok" << endl; }
template <class T>
void printv(const vector<T> &v) {
    for (int i = 0; i < v.size(); i++) cout << v[i] << (i + 1 == v.size() ? '\n' : ' ');
}
template <class T>
void readv(vector<T> &v) {
    for (int i = 0; i < v.size(); i++) cin >> v[i];
}
int main() {
    ios::sync_with_stdio(0);
    cin.tie(0);
    ll n, f, l;
    cin >> n >> f >> l;
    V<ll> x(n + 1), v(n), w(n);
    x[0] = 0;
    for (int i = 0; i < n; i++) {
        cin >> x[i + 1] >> v[i] >> w[i];
    }
    V<V<ll>> dp(n + 1, V<ll>(f + 1, INF));
    dp[0][f] = 0;
    for (int i = 0; i < n; i++) {
        for (int j = 0; j <= f; j++) {
            if (dp[i][j] == INF) continue;
            if (j - (x[i + 1] - x[i]) < 0) continue;
            int to = j - (x[i + 1] - x[i]);
            chmin(dp[i + 1][to], dp[i][j]);
            chmin(dp[i + 1][min(f, to + v[i])], dp[i][j] + w[i]);
        }
    }
    ll res = INF;
    for (int i = 0; i <= f; i++) {
        if (dp[n][i] != INF && i - (l - x[n]) >= 0) {
            chmin(res, dp[n][i]);
        }
    }
    cout << (res == INF ? -1 : res) << '\n';
}