#include <iostream>
#include <cstdio>
#include <string>
#include <cstring>
#include <deque>
#include <list>
#include <queue>
#include <stack>
#include <vector>
#include <utility>
#include <algorithm>
#include <map>
#include <set>
#include <complex>
#include <cmath>
#include <limits>
#include <climits>
#include <ctime>
#include <cassert>
#include <numeric>
#include <functional>
#include <bitset>

using namespace std;
using lint = long long int;
long long int INF = 1001001001001001LL;
int inf = 1000000007;
long long int MOD = 1000000007LL;
double PI = 3.1415926535897932;

template<typename T1,typename T2>inline void chmin(T1 &a,const T2 &b){if(a>b) a=b;}
template<typename T1,typename T2>inline void chmax(T1 &a,const T2 &b){if(a<b) a=b;}

#define ALL(a) a.begin(),a.end()
#define RALL(a) a.rbegin(),a.rend()

/* do your best */

int main() {
  
  lint n, V, l; cin >> n >> V >> l;
  vector<lint> x(n);
  vector<lint> v(n);
  vector<lint> w(n);
  for (int i = 0; i < n; i++) {
    cin >> x[i] >> v[i] >> w[i];
  }

  vector<vector<lint>> dp(n + 1, vector<lint> (V + 1, INF));
  if (V < x[0]) {
    cout << -1 << endl;
    return 0;
  }

  dp[0][V - x[0]] = 0;

  for (int i = 0; i < n; i++) {
    for (int j = 0; j <= V; j++) {
      if (dp[i][j] == INF) continue;
      // 補給せずに行く
      lint nxtPos = l;
      if (i != n - 1) nxtPos = x[i + 1];
      lint dist = nxtPos - x[i];
      if (j >= dist) dp[i + 1][j - dist] = min(dp[i + 1][j - dist], dp[i][j]);

      // 補給していく
      lint nxtV = min(V, j + v[i]);
      lint cost = w[i];
      if (nxtV >= dist) dp[i + 1][nxtV - dist] = min(dp[i + 1][nxtV - dist], dp[i][j] + cost);
    }
  }

  lint ans = INF;
  for (int j = 0; j <= V; j++) ans = min(ans, dp[n][j]);
  if (ans == INF) ans = -1;
  cout << ans << endl;

  return 0;
}