#include <iostream>
#include <string>
#include <cstdlib>
#include <cmath>
#include <vector>
#include <map>
#include <set>
#include <algorithm>
#include <queue>
#include <stack>
#include <functional>
#include <bitset>
#include <assert.h>
using namespace std;
typedef long long ll;
typedef vector<ll> vl;
typedef vector<vl> vvl;
typedef vector<char> vc;
typedef vector<string> vs;
typedef vector<bool> vb;
typedef vector<double> vd;
typedef pair<ll,ll> P;
typedef vector<P> vpl;
typedef tuple<ll,ll,ll> tapu;
#define rep(i,n) for(ll i=0; i<(n); i++)
#define REP(i,a,b) for(int i=(a); i<(b); i++)
#define all(x) (x).begin(), (x).end()
#define rall(x) (x).rbegin(), (x).rend()
const int inf = 1<<30;
const ll linf = 1LL<<62;
const int MAX = 510000;
ll dy[8] = {0,1,0,-1,1,-1,1,-1};
ll dx[8] = {1,0,-1,0,1,-1,-1,1};
const double pi = acos(-1);
const double eps = 1e-7;
template<typename T1,typename T2> inline bool chmin(T1 &a,T2 b){
	if(a>b){
		a = b; return true;
	}
	else return false;
}
template<typename T1,typename T2> inline bool chmax(T1 &a,T2 b){
	if(a<b){
		a = b; return true;
	}
	else return false;
}
template<typename T1,typename T2> inline void print2(T1 a, T2 b){cout << a << " " << b << "\n";}
template<typename T1,typename T2,typename T3> inline void print3(T1 a, T2 b, T3 c){
	cout << a << " " << b << " " << c << "\n";
}
const int mod = 1e9 + 7;
//const int mod = 998244353;

ll dp[2020][2020][2];

int main(){
	ll N,V,L; cin >> N >> V >> L;
	vl x(N+1),v(N),w(N);
	rep(i,N+1) rep(j,V+1) rep(k,2) dp[i][j][k] = inf;
	rep(j,V+1) dp[0][j][0] = 0;
	x[0] = 0;
	rep(i,N) cin >> x[i+1] >> v[i] >> w[i];
	rep(i,N){
		ll t = x[i+1]-x[i];
		ll limit = V;
		rep(j,V+1){
			if(j+t<=V && min(dp[i][j+t][0],dp[i][j+t][1]) != inf){
				chmin(dp[i+1][j][0],min(dp[i][j+t][0],dp[i][j+t][1]));
			}
			if(dp[i+1][max(0LL,j-v[i])][0] != inf){
				chmin(dp[i+1][j][1],dp[i+1][max(0LL,j-v[i])][0]+w[i]);
			}
		}
	}
	ll ans = inf;
	REP(j,L-x[N],V+1) chmin(ans,min(dp[N][j][0],dp[N][j][1]));
	if(ans != inf) cout << ans << endl;
	else cout << -1 << endl;
}