#include <bits/stdc++.h>
#define rep(i, a) for (int i = (int)0; i < (int)a; ++i)
#define rrep(i, a) for (int i = (int)a - 1; i >= 0; --i)
#define REP(i, a, b) for (int i = (int)a; i < (int)b; ++i)
#define RREP(i, a, b) for (int i = (int)a - 1; i >= b; --i)
#define pb push_back
#define eb emplace_back
#define all(x) x.begin(), x.end()
#define rall(x) x.rbegin(), x.rend()
#define popcount __builtin_popcount
using ll = long long;
constexpr ll mod = 1e9 + 7;
constexpr ll INF = 1LL << 60;

template <class T>
inline bool chmin(T &a, T b)
{
	if (a > b)
	{
		a = b;
		return true;
	}
	return false;
}
template <class T>
inline bool chmax(T &a, T b)
{
	if (a < b)
	{
		a = b;
		return true;
	}
	return false;
}

ll gcd(ll n, ll m)
{
	ll tmp;
	while (m != 0)
	{
		tmp = n % m;
		n = m;
		m = tmp;
	}
	return n;
}

ll lcm(ll n, ll m)
{
	return abs(n) / gcd(n, m) * abs(m); //gl=xy
}

using namespace std;

void solve()
{
	ll n,V,l;
	cin>>n>>V>>l;
	vector<ll>x(n+2),v(n+2),w(n+2);
	REP(i,1,n+1){
		cin>>x[i]>>v[i]>>w[i];
	}
	x[n+1]=l;
	vector<vector<ll>>dp(n+5,vector<ll>(V+1,INF));
	dp[0][V]=0;
	rep(i,n+1){
		rep(j,V+1){
			if(dp[i][j]==INF)continue;
			if(j-(x[i+1]-x[i])<0)continue;//そもそも到達不可
			chmin(dp[i+1][min(V,j-(x[i+1]-x[i])+v[i+1])],dp[i][j]+w[i+1]);
			chmin(dp[i+1][j-(x[i+1]-x[i])],dp[i][j]);
		}
	}
	ll ans=INF;
	rep(i,V+1)chmin(ans,dp[n+1][i]);
	if(ans==INF)cout<<-1<<"\n";
	else cout<<ans<<"\n";
}

int main()
{
	ios::sync_with_stdio(false);
	cin.tie(0);
	cout << fixed << setprecision(15);
	solve();
	return 0;
}