#include<bits/stdc++.h>
#define ALL(v) std::begin(v),std::end(v)
using lint=long long;
using ld=long double;
template<class T>using numr=std::numeric_limits<T>;
void cmn(lint&x,lint y){if(x>y)x=y;}
int main(){
    std::cin.tie(nullptr);std::ios_base::sync_with_stdio(false);
    std::cout.setf(std::ios_base::fixed);std::cout.precision(15);
    lint inf=numr<lint>::max();
    lint n,V,L;std::cin>>n>>V>>L;
    std::vector<std::tuple<lint,lint,lint>>a(n+2);
    a.at(0)={0,0,0},a.at(n+1)={L,0,0};
    for(lint i=1;i<=n;i++){
        lint x,v,w;std::cin>>x>>v>>w;
        a.at(i)={x,v,w};
    }
    std::vector<lint>dp(V+1,0);
    for(lint i=1;i<=n+1;i++){
        lint x,v,w;std::tie(x,v,w)=a.at(i);
        x-=std::get<0>(a.at(i-1));
        if(V<x){
            std::cout<<-1<<'\n';
            return 0;
        }
        std::copy(dp.begin()+x,dp.end(),dp.begin());
        std::fill(dp.end()-x,dp.end(),inf);
        for(lint j=V;j>0;j--){
            if(j<V)cmn(dp.at(j),dp.at(j+1));
            if(v<=j&&dp.at(j-v)!=inf)cmn(dp.at(j),dp.at(j-v)+w);
        }
    }
    lint ans=dp.at(0);
    if(ans==inf)ans=-1;
    std::cout<<ans<<'\n';
}