#include <bits/stdc++.h>
using namespace std;
using ll = long long;

int main(){
    ios::sync_with_stdio(false);
    cin.tie(0);
    int n, V, L;
    cin >> n >> V >> L;
    vector<int> x(n + 2), v(n + 1), w(n + 1);
    for(int i = 1; i <= n; i++){
        cin >> x[i] >> v[i] >> w[i];
    }
    x[n + 1] = L;
    vector<vector<ll>> dp(n + 2, vector<ll>(V + 1, 1ll << 60));
    dp[0][V] = 0;
    for(int i = 0; i <= n; i++){
        int d = x[i + 1] - x[i];
        for(int j = 0; j <= V; j++){
            dp[i][min(V, j + v[i])] = min(dp[i][min(V, j + v[i])], dp[i][j] + w[i]);
            if(j >= d) dp[i + 1][j - d] = min(dp[i + 1][j - d], dp[i][j]);
        }
    }
    ll ans = *min_element(dp.back().begin(), dp.back().end());
    cout << (ans >> 60 ? -1 : ans) << '\n';
}