#include <bits/stdc++.h>
#define loop(n) for (int ngtkana_is_genius = 0; ngtkana_is_genius < int(n); ngtkana_is_genius++)
#define rep(i, begin, end) for(int i = int(begin); i < int(end); i++)
#define all(v) v.begin(), v.end()
#define rand(l, r) std::uniform_int_distribution<>(l, r)(mt)
using lint = long long;
auto cmn = [](auto& a, auto b){if (a > b) {a = b; return true;} return false;};
auto cmx = [](auto& a, auto b){if (a < b) {a = b; return true;} return false;};
void debug_impl() { std::cerr << std::endl; }
template <typename Head, typename... Tail>
void debug_impl(Head head, Tail... tail){
  std::cerr << " " << head;
  debug_impl(tail...);
}
#ifndef STOPIT
#define debug(...)\
  std::cerr << std::boolalpha << "[" << #__VA_ARGS__ << "]:";\
  debug_impl(__VA_ARGS__);\
  std::cerr << std::noboolalpha;
#else
#define debug 0;
#endif

bool bat (int       x, int j) {return (x >> j) & 1  ;}
bool bat (long long x, int j) {return (x >> j) & 1LL;}

int main() {
  std::cin.tie(0); std::cin.sync_with_stdio(false);
  int n, V, L;
  std::cin >> n >> V >> L;
  std::vector< int > x(n), v(n), w(n);
  rep(i, 0, n) {
    std::cin >> x.at(i) >> v.at(i) >> w.at(i);
  }
  x.push_back(L);
  v.push_back(0);
  w.push_back(0);

  constexpr auto inf = 1LL << 60;
  auto ret = inf;
  auto N = 1 << n;
  rep(bs, N, 2 * N) {
    auto life = V, time = 0;
    auto cost = 0LL;
    auto ng = false;
    rep(i, 0, n + 1) {
      if (!bat(bs, i)) continue;
      life -= x.at(i) - time;
      if (life < 0) {
        ng = true;
        break;
      }
      life = std::min(V, life + v.at(i));
      cost += w.at(i);
      time = x.at(i);
    }
    if (!ng) {
      cmn(ret, cost);
    }
  }

  if (ret == inf) ret = -1;
  std::cout << ret << std::endl;
  return 0;
}