#include <bits/stdc++.h>
using namespace std;
#define rep(i,n) for(int i = 0; i < (n);i++)
#define sz(x) int(x.size())
typedef long long ll;
typedef long double ld;
typedef pair<int,int> P;
typedef pair<ll, int> PL;
constexpr ll INF = (1LL << 60);
typedef tuple<int,int,int> TP;

int main() {
  int n, V, L;
  cin >> n >> V >> L;
  vector<TP> g;
  for (int i = 0; i < n; i++) {
    int x, v, w;
    cin >> x >> v >> w;
    g.emplace_back(make_tuple(x, v, w));
  }
  g.emplace_back(make_tuple(L, 0, 0));

  vector<ll> dp(V + 1, INF);
  dp[V] = 0;
  int prev = 0;
  for (int i = 0; i < n + 1; i++) {
    int x, v, w;
    tie(x, v, w) = g[i];
    int dif = x - prev;
    for (int j = 0; j <= V; j++) {
      if (j - dif >= 0) dp[j - dif] = dp[j];
      dp[j] = INF;
    }
    for (int j = V; j >= 0; j--) {
      int to = min(V, j + v);
      dp[to] = min(dp[to], dp[j] + w);
    }
    prev = x;
  }
  ll res = INF;
  for (int i = V; i >= 0; i--) {
    res = min(res, dp[i]);
  }
  cout << (res == INF ? -1 : res) << endl;
  return 0;
}