#include<bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef long double ld;
typedef pair<ll,ll> P;
typedef pair<int,int> Pi;
#define rep(i,n) for(ll i=0;i<n;i++)
#define FOR(i,a,b) for(ll i=a;i<b;i++)
#define fi first
#define se second
#define endl "\n"

template<typename T> inline bool chmax(T &a, T b){if(a<b){a=b;return true;}return false;}
template<typename T> inline bool chmin(T &a, T b){if(a>b){a=b;return true;}return false;}
template<typename T> ostream& operator<<(ostream& s,const complex<T>& d) {return s<<"("<<d.real()<<", "<<d.imag()<< ")";}
template<typename T1, typename T2> ostream& operator<<(ostream& s,const pair<T1,T2>& d) {return s<<"("<<d.first<<", "<<d.second<<")";}
template<typename T> ostream& operator<<(ostream& s, const vector<T>& d){int len=d.size();rep(i,len){s<<d[i];if(i<len-1) s<<" ";}return s;}
template<typename T> ostream& operator<<(ostream& s,const vector<vector<T>>& d){int len=d.size();rep(i,len){s<<d[i]<<endl;}return s;}
template<typename T> ostream& operator<<(ostream& s,const set<T>& v){s<<"{ ";for(auto itr=v.begin();itr!=v.end();++itr) {if (itr!=v.begin()) {s<< ", ";}s<<(*itr);}s<<" }";return s;}
template<typename T1, typename T2> ostream& operator<<(ostream& s,const map<T1,T2>& m){s<<"{"<<endl;for(auto itr=m.begin();itr!=m.end();++itr){s<<" "<<(*itr).first<<" : "<<(*itr).second<<endl;}s<<"}"<<endl;return s;}

const ll mod=1e9+7;
const ll inf=1e17;
const int INF=1e9;
const double PI=acos(-1);
const double EPS=1e-10;

int main(){
	cin.tie(0);ios::sync_with_stdio(false);
	ll n,V,l;
	cin>>n>>V>>l;
	vector<ll> x(n+2,0),v(n+2,0),w(n+2,0);
	FOR(i,1,n+1){
		cin>>x[i]>>v[i]>>w[i];
	}
	x[n+1]=l;
	vector<vector<ll>> dp(n+2,vector<ll>(V+1,inf));
	dp[0][V]=0;
	rep(i,n+1)rep(j,V+1){
		if(dp[i][j]==inf) continue;
		ll ne=x[i+1]-x[i];
		if(j>=ne){
			chmin(dp[i+1][j-ne],dp[i][j]);
		}
		ll nj=min(V,j+v[i]);
		if(nj>=ne){
			chmin(dp[i+1][nj-ne],dp[i][j]+w[i]);
		}
	}
	ll ans=inf;
	rep(j,V+1){
		chmin(ans,dp[n+1][j]);
	}
	if(ans==inf) cout<<-1<<endl;
	else cout<<ans<<endl;
}