#include <bits/stdc++.h>
using namespace std;
template <class F> class y_combinator {
    F f;

   public:
    y_combinator(F&& f) : f(std::forward<F>(f)) {}
    template <class... Args> auto operator()(Args&&... args) const { return f(*this, std::forward<Args>(args)...); }
};
using ll = long long;
using ld = long double;
using u8 = uint8_t;
using u32 = uint32_t;
using u64 = uint64_t;
using vi = vector<int>;
using vl = vector<ll>;
using pii = pair<int, int>;
using pll = pair<ll, ll>;
template <class T, class U = std::less<T>> using prique = std::priority_queue<T, std::vector<T>, U>;
inline constexpr int popcnt(u64 x) noexcept { return __builtin_popcountll(x); }
template <class T> T floor(T a, T b) noexcept { return a / b - (a % b && (a ^ b) < 0); }
template <class T> T ceil(T a, T b) noexcept { return floor(a + b - 1, b); }
template <class T> bool chmin(T& x, const T& y) noexcept { return (x > y ? x = y, true : false); }
template <class T> bool chmax(T& x, const T& y) noexcept { return (x < y ? x = y, true : false); }
#define overload4(a, b, c, d, e, ...) e
#define rep1(a) for (long long _i = 0; _i < (a); _i++)
#define rep2(i, a) for (long long i = 0; i < (a); i++)
#define rep3(i, a, b) for (long long i = (a); i < (b); i++)
#define rep4(i, a, b, c) for (long long i = (a); i < (b); i += (c))
#define rep(...) overload4(__VA_ARGS__, rep4, rep3, rep2, rep1)(__VA_ARGS__)
#define rrep(i, a, b, c) for (long long i = (a); i > (b); i += (c))
#define all(x) std::begin(x), std::end(x)
#define rall(x) std::rbegin(x), std::rend(x)
#define len(x) (long long)(size(x))
#define pb push_back
#ifndef LOCAL
#define debug(...)
#endif

#include <atcoder/modint>
using mint = atcoder::modint998244353;
int N, V, L;
int x[2020], v[2020], w[2020];
ll dp[2][2020];
void run_case() {
    cin >> N >> V >> L;
    rep(i, N) cin >> x[i] >> v[i] >> w[i];
    int cur = 0;
    rep(i, 2020) dp[cur][i] = 1e18;
    dp[cur][V] = 0;
    rep(i, N) {
        int nxt = 1 - cur;
        rep(j, 2020) dp[nxt][j] = 1e18;
        int px = (i == 0 ? 0 : x[i - 1]);
        int d = x[i] - px;
        rep(j, 2020) if (dp[cur][j] != 1e18 && j >= d) {
            chmin(dp[nxt][j - d], dp[cur][j]);
            chmin(dp[nxt][min<int>(j - d + v[i], V)], dp[cur][j] + w[i]);
        }
        cur = nxt;
    }
    ll ans = 1e18;
    rep(i, 2020) if (i >= L-x[N-1]) chmin(ans, dp[cur][i]);
    cout << (ans == 1e18 ? -1 : ans) << "\n";
}
int main() {
    std::ios_base::sync_with_stdio(false);
    std::cin.tie(nullptr);
    std::fixed(std::cout).precision(16);
    int T = 1;
    while (T--) run_case();
    return 0;
}