#include <bits/stdc++.h>
#include <iomanip>
using namespace std;
#define reps(i,s,n) for(int i = s; i < n; i++)
#define rep(i,n) reps(i,0,n)
#define Rreps(i,n,e) for(int i = n - 1; i >= e; --i)
#define Rrep(i,n) Rreps(i,n,0)
#define ALL(a) a.begin(), a.end()
#define fi first
#define se second
typedef long long ll;
typedef vector<ll> vec;
typedef vector<vec> mat;

ll N,M,H,W,Q,K,A,B;
string S;
const ll MOD = 998244353;
//const ll MOD = (1e+9) + 7;
const ll INF = 1LL<<60;
typedef pair<ll, ll> P;

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

int main() {
    ll V, L;
    cin>>N>>V>>L;
    vec x(N), v(N), w(N);
    rep(i,N) cin>>x[i]>>v[i]>>w[i];
    ++N;
    x.push_back(L);
    v.push_back(0);
    w.push_back(0);
    mat dp(N + 1, vec(V + 1, INF));
    dp[0][V] = 0;
    rep(i,N){
        rep(j,V + 1){
            ll dist = (i == 0 ? x[0] : x[i] - x[i-1]);
            if(dist <= j){
                chmin(dp[i+1][j - dist], dp[i][j]);
                chmin(dp[i+1][min(V, j - dist + v[i])], dp[i][j] + w[i]);
            }
            //cout<<(dp[i][j] == INF ? -1 : dp[i][j])<<' ';
        }
        //cout<<endl;
    }
    ll ans = INF;
    rep(j,V + 1) chmin(ans, dp[N][j]);
    cout<<(ans == INF ? -1 : ans)<<endl;
}