#define _USE_MATH_DEFINES
#include <bits/stdc++.h>
using namespace std;
#define FOR(i,m,n) for(int i=(m);i<(n);++i)
#define REP(i,n) FOR(i,0,n)
#define ALL(v) (v).begin(),(v).end()
using ll = long long;
const int INF = 0x3f3f3f3f;
const ll LINF = 0x3f3f3f3f3f3f3f3fLL;
const double EPS = 1e-8;
const int MOD = 1000000007;
// const int MOD = 998244353;
const int dy[] = {1, 0, -1, 0}, dx[] = {0, -1, 0, 1};
const int dy8[] = {1, 1, 0, -1, -1, -1, 0, 1}, dx8[] = {0, -1, -1, -1, 0, 1, 1, 1};
template <typename T, typename U> inline bool chmax(T &a, U b) { return a < b ? (a = b, true) : false; }
template <typename T, typename U> inline bool chmin(T &a, U b) { return a > b ? (a = b, true) : false; }
struct IOSetup {
  IOSetup() {
    cin.tie(nullptr);
    ios_base::sync_with_stdio(false);
    cout << fixed << setprecision(20);
  }
} iosetup;

int main() {
  int n, V, l; cin >> n >> V >> l;
  n += 2;
  vector<int> x(n), v(n), w(n);
  x[0] = v[0] = w[0] = 0;
  x[n - 1] = l; v[n - 1] = w[n - 1] = 0;
  FOR(i, 1, n - 1) cin >> x[i] >> v[i] >> w[i];
  vector dp(n, vector(V + 1, LINF));
  dp[0][V] = 0;
  FOR(i, 1, n) {
    REP(j, V + 1) {
      if (j + x[i] - x[i - 1] > V) break;
      dp[i][j] = dp[i - 1][j + x[i] - x[i - 1]];
    }
    for (int j = V; j >= 0; --j) chmin(dp[i][min(j + v[i], V)], dp[i][j] + w[i]);
  }
  ll ans = *min_element(ALL(dp[n - 1]));
  cout << (ans == LINF ? -1 : ans) << '\n';
  return 0;
}