#pragma GCC target("avx")
#pragma GCC optimize("O3")
#pragma GCC optimize("unroll-loops")
#include "bits/stdc++.h"
#pragma warning(disable:4996)
using namespace std;
#define int long long
#define rep(i,n) for(int i=0;i<n;i++)

int x[2005], v[2006], w[2005];
int dp[2005][2005];
signed main() {
	int n, V, l; cin >> n >> V >> l;
	rep(i, n)cin >> x[i+1] >> v[i] >> w[i];

	rep(i, n + 1)rep(j, V + 1)dp[i][j] = 1e17;
	dp[0][0] = 0;
	rep(i, n) {
		rep(j, V + 1) {
			if (dp[i][j] == 1e17)continue;
			if (x[i + 1] - x[i] + j <= V)dp[i + 1][j + x[i + 1] - x[i]] = min(dp[i + 1][j + x[i + 1] - x[i]], dp[i][j]);
		}
		rep(j, V + 1) {
			dp[i + 1][max(0ll, j - v[i])] = min(dp[i + 1][max(0ll, j - v[i])], dp[i + 1][j] + w[i]);
		}
	}
	int ans = 1e17;
	for(int i=0;i<=V-l+x[n];i++)ans = min(ans, dp[n][i]);
	if (ans == 1e17)ans = -1;
	cout << ans << endl;
}