#pragma GCC optimize ("Ofast")
#include<bits/stdc++.h>
using namespace std;
template<class S, class T> inline S min_L(S a,T b){
  return a<=b?a:b;
}
inline int my_getchar_unlocked(){
  static char buf[1048576];
  static int s = 1048576;
  static int e = 1048576;
  if(s == e && e == 1048576){
    e = fread_unlocked(buf, 1, 1048576, stdin);
    s = 0;
  }
  if(s == e){
    return EOF;
  }
  return buf[s++];
}
inline void rd(int &x){
  int k;
  int m=0;
  x=0;
  for(;;){
    k = my_getchar_unlocked();
    if(k=='-'){
      m=1;
      break;
    }
    if('0'<=k&&k<='9'){
      x=k-'0';
      break;
    }
  }
  for(;;){
    k = my_getchar_unlocked();
    if(k<'0'||k>'9'){
      break;
    }
    x=x*10+k-'0';
  }
  if(m){
    x=-x;
  }
}
struct MY_WRITER{
  char buf[1048576];
  int s;
  int e;
  MY_WRITER(){
    s = 0;
    e = 1048576;
  }
  ~MY_WRITER(){
    if(s){
      fwrite_unlocked(buf, 1, s, stdout);
    }
  }
}
;
MY_WRITER MY_WRITER_VAR;
void my_putchar_unlocked(int a){
  if(MY_WRITER_VAR.s == MY_WRITER_VAR.e){
    fwrite_unlocked(MY_WRITER_VAR.buf, 1, MY_WRITER_VAR.s, stdout);
    MY_WRITER_VAR.s = 0;
  }
  MY_WRITER_VAR.buf[MY_WRITER_VAR.s++] = a;
}
inline void wt_L(char a){
  my_putchar_unlocked(a);
}
inline void wt_L(int x){
  int s=0;
  int m=0;
  char f[10];
  if(x<0){
    m=1;
    x=-x;
  }
  while(x){
    f[s++]=x%10;
    x/=10;
  }
  if(!s){
    f[s++]=0;
  }
  if(m){
    my_putchar_unlocked('-');
  }
  while(s--){
    my_putchar_unlocked(f[s]+'0');
  }
}
inline void wt_L(long long x){
  int s=0;
  int m=0;
  char f[20];
  if(x<0){
    m=1;
    x=-x;
  }
  while(x){
    f[s++]=x%10;
    x/=10;
  }
  if(!s){
    f[s++]=0;
  }
  if(m){
    my_putchar_unlocked('-');
  }
  while(s--){
    my_putchar_unlocked(f[s]+'0');
  }
}
template<class S, class T> inline S chmin(S &a, T b){
  if(a>b){
    a=b;
  }
  return a;
}
int N;
int V;
int L;
int X[2002];
int F[2002];
int W[2002];
long long dp[2002];
long long nx[2002];
int main(){
  int i;
  int j;
  int k;
  int d;
  long long res = 4611686016279904256LL;
  rd(N);
  rd(V);
  rd(L);
  N += 2;
  for(i=(1);i<(N-1);i++){
    rd(X[i]);
    rd(F[i]);
    rd(W[i]);
  }
  X[N-1] = L;
  for(k=(1);k<(N);k++){
    for(i=(0);i<(V+1);i++){
      nx[i] = 4611686016279904256LL;
    }
    d = X[k] - X[k-1];
    for(i=(d);i<(V+1);i++){
      chmin(nx[i-d], dp[i]);
      chmin(nx[min_L(V, i-d+F[k])], dp[i] + W[k]);
    }
    for(i=(0);i<(V+1);i++){
      dp[i] = nx[i];
    }
  }
  for(i=(0);i<(V+1);i++){
    chmin(res, dp[i]);
  }
  if(res==4611686016279904256LL){
    wt_L(-1);
    wt_L('\n');
  }
  else{
    wt_L(res);
    wt_L('\n');
  }
  return 0;
}
// cLay varsion 20200419-1

// --- original code ---
// int N, V, L, X[2002], F[2002], W[2002];
// ll dp[2002], nx[2002];
// {
//   int i, j, k, d;
//   ll res = ll_inf;
//   rd(N,V,L);
//   N += 2;
//   rep(i,1,N-1) rd(X[i], F[i], W[i]);
//   X[N-1] = L;
// 
//   rep(k,1,N){
//     rep(i,V+1) nx[i] = ll_inf;
//     d = X[k] - X[k-1];
//     rep(i,d,V+1){
//       nx[i-d] <?= dp[i];
//       nx[min(V,i-d+F[k])] <?= dp[i] + W[k];
//     }
//     rep(i,V+1) dp[i] = nx[i];
//   }
// 
//   rep(i,V+1) res <?= dp[i];
//   wt(if[res==ll_inf,-1,res]);
// }