#include <bits/stdc++.h>

#define M_PI       3.14159265358979323846   // pi

using namespace std;
typedef long long ll;
typedef unsigned long long ull;
typedef vector<ll> VI;
typedef pair<ll, ll> P;
typedef tuple<ll, ll, ll> t3;
typedef tuple<ll, ll, ll, ll> t4;
typedef tuple<ll, ll, ll, ll, ll> t5;

#define rep(a,n) for(ll a = 0;a < n;a++)
#define repi(a,b,n) for(ll a = b;a < n;a++)

using namespace std;

static const ll INF = 1e15;

const ll mod = 1000000007;

template<typename T>
void chmin(T & ref, const T  value) {
	if (ref > value) ref = value;
}

int main() {
	ll n, v, l;
	cin >> n >> v >> l;
	vector<ll> xs(n+1, 0), vs(n+1,0), ws(n+1,0);
	rep(i, n) {
		cin >> xs[i+1] >> vs[i+1] >> ws[i+1];
	}
	vector<vector<ll>> dp(n + 1, vector<ll>(v + 1, INF));
	dp[0][v] = 0;
	rep(i, n) {
		ll d = xs[i + 1] - xs[i];
		rep(j, v + 1) {
			if (j >= d) {
				chmin(dp[i + 1][j - d], dp[i][j]);
				auto nv = min(v, j - d + vs[i + 1]);
				chmin(dp[i + 1][nv], dp[i][j] + ws[i + 1]);
			}
		}
	}
	ll low = INF;
	for (int j = l - xs[n]; j < v + 1;j++)  {
		chmin(low, dp[n][j]);
	}
	if (low == INF) {
		cout << -1 << endl;
	}
	else {
		cout << low << endl;
	}
	return 0;
}