#include <bits/stdc++.h>
#define rep(i,n) for(int i=0;i<n;i++)
using namespace std;
using ll =  long long ;
using P = pair<int,int> ;
const ll INF = 1e10;
const int MOD = 1000000007;

struct gas{
    int x,v,w;
};

int main(){
    int N,V,L;
    cin >> N >> V >> L;
    vector<gas> gass(N);
    rep(i,N) cin >> gass[i].x >> gass[i].v >> gass[i].w;
    vector<vector<ll>> dp(N+1,vector<ll>(V+1,INF));
    dp[0][V] = 0;
    for(int i=1;i<=N;i++){
        ll d = (i==1 ? gass[i-1].x : gass[i-1].x - gass[i-2].x);
        ll mn = INF;
        rep(j,V+1){
            if(d+V-gass[i-1].v <= j && V - gass[i-1].v >= 0) mn = min(mn,dp[i-1][j]);

            if(j+d <= V) dp[i][j] = dp[i-1][j+d];
            if(j-gass[i-1].v >= 0 && j+d-gass[i-1].v <= V) dp[i][j] = min(dp[i][j],dp[i-1][j+d-gass[i-1].v] + gass[i-1].w);
            if(j==V) dp[i][j] = min(dp[i][j],mn + gass[i-1].w);
        }
    }
    ll d = L - gass[N-1].x;
    ll ans = INF;
    for(ll i=d;i<=V;i++){
        ans = min(ans,dp[N][i]);
    }  
    cout << (ans==INF ? -1 : ans) << endl;
    /*
    rep(i,N+1){
        rep(j,V+1) cout << dp[i][j] << " ";
        cout << endl;
    }*/
    return 0;
}