#include <cstdio>
#include <cstring>
#include <iostream>
#include <string>
#include <cmath>
#include <bitset>
#include <vector>
#include <map>
#include <set>
#include <queue>
#include <deque>
#include <algorithm>
#include <complex>
#include <unordered_map>
#include <unordered_set>
#include <random>
#include <cassert>
#include <fstream>
#include <utility>
#include <functional>
#include <time.h>
#include <stack>
#include <array>
#define popcount __builtin_popcount
using namespace std;
typedef long long int ll;
typedef pair<int, int> P;

int main()
{
	int n, V, l;
	cin>>n>>V>>l;
	int x[2020], v[2020]; ll w[2020];
	for(int i=1; i<=n; i++) cin>>x[i]>>v[i]>>w[i];
	x[0]=0, x[n+1]=l;
	v[0]=v[n+1]=0, w[0]=w[n+1]=0;
	ll dp[2020][2020];
	const ll INF=1e18;
	for(int i=0; i<=n+1; i++){
		for(int j=0; j<=V; j++) dp[i][j]=INF;
	}
	dp[0][V]=0;
	for(int i=0; i<=n; i++){
		for(int j=0; j<=V; j++){
			if(j-(x[i+1]-x[i])>=0){
				dp[i+1][j-(x[i+1]-x[i])]=min(dp[i+1][j-(x[i+1]-x[i])], dp[i][j]);
				dp[i+1][min(V, j-(x[i+1]-x[i])+v[i+1])]=min(dp[i+1][min(V, j-(x[i+1]-x[i])+v[i+1])], dp[i][j]+w[i+1]);
			}
		}
	}
	ll ans=INF;
	for(int i=0; i<=V; i++) ans=min(ans, dp[n+1][i]);
	if(ans>=INF/2) cout<<-1<<endl;
	else cout<<ans<<endl;
	return 0;
}