#include<bits/stdc++.h>
using namespace std;
#define ALL(x) x.begin(),x.end()
#define rep(i,n) for(int i=0;i<(n);i++)
#define debug(v) cout<<#v<<":";for(auto x:v){cout<<x<<' ';}cout<<endl;
#define INF 1000000000
#define mod 1000000007
using ll=long long;
const ll LINF=1001002003004005006ll;
int dx[]={1,0,-1,0};
int dy[]={0,1,0,-1};
// ll gcd(ll a,ll b){return b?gcd(b,a%b):a;}
template<class T>bool chmax(T &a,const T &b){if(a<b){a=b;return true;}return false;}
template<class T>bool chmin(T &a,const T &b){if(b<a){a=b;return true;}return false;}

signed main(){
    cin.tie(0);
    ios::sync_with_stdio(0);
    
    // dp[i][j]: i番目まで，燃料jの最小コスト
    
    ll N,V,L;cin>>N>>V>>L;

    ll dp[N+2][V+1];
    rep(i,N+2)rep(j,V+1)dp[i][j]=LINF;

    dp[0][V]=0;

    ll pre=0;
    rep(i,N){
        ll x,v,w;cin>>x>>v>>w;
        ll dis=x-pre;
        for(int j=0;j+dis<=V;j++){
            dp[i+1][j]=dp[i][j+dis];
        }
        bool check[V+1]={};
        for(int j=0;j<=V;j++){
            if(chmin(dp[i+1][min(V,j+v)],check[j]?dp[i+1][j]:dp[i+1][j]+w)) check[min(V,j+v)]=true;
        }
        // for(int j=0;j<=V;j++) cout<<dp[i+1][j]<<" ";cout<<endl;
        pre=x;
    }

    ll ans=LINF;
    ll dis=L-pre;
    for(int i=0;i+dis<=V;i++){
        dp[N+1][i]=dp[N][i+dis];
    }
    rep(i,V+1) chmin(ans,dp[N+1][i]);
    cout<<(ans<LINF?ans:-1)<<endl;
    return 0;
}