#include <bits/stdc++.h>
using namespace std::literals::string_literals;
using i64 = std::int_fast64_t;
using std::cout;
using std::cerr;
using std::endl;
using std::cin;

template<typename T>
std::vector<T> make_v(size_t a){return std::vector<T>(a);}

template<typename T,typename... Ts>
auto make_v(size_t a,Ts... ts){
  return std::vector<decltype(make_v<T>(ts...))>(a,make_v<T>(ts...));
}

int main() {
	int n, v, l; scanf("%d%d%d", &n, &v, &l);
	std::vector<int> x(n + 1), y(n + 1);
	std::vector<i64> z(n + 1);
	for(int i = 1; i <= n; i++) scanf("%d%d%lld", &x[i], &y[i], &z[i]);
	x.push_back(l);
	y.push_back(0);
	z.push_back(0);

	std::vector<i64> dp(v + 1, 0);
	for(int i = 1; i < (int)x.size(); i++) {
		std::vector<i64> to(v + 1, 1LL << 60);

		int diff = x[i] - x[i  -1];
		for(int j = x[i] - x[i - 1]; j < v + 1; j++) {
			to[j - diff] = std::min(to[j - diff], dp[j]);
			if(j - diff + y[i] < v + 1) to[j - diff + y[i]] = std::min(to[j - diff + y[i]], dp[j] + z[i]);
		}
		dp.swap(to);
	}

	i64 ans = *std::min_element(begin(dp), end(dp));
	if(ans == 1LL << 60) ans = -1;
	printf("%lld\n", ans);
	return 0;
}