#include <bits/stdc++.h> using namespace std; using ll = long long; template <class T, class U> using Pa = pair<T, U>; template <class T> using vec = vector<T>; template <class T> using vvec = vector<vec<T>>; void chmin(ll &a,ll b){if(a>b) a = b;} int main(){ cin.tie(0); ios::sync_with_stdio(false); int N,V,L; cin >> N >> V >> L; vec<int> x(N+2),v(N+2),w(N+2); for(int i=1;i<=N;i++) cin >> x[i] >> v[i] >> w[i]; ll inf = 1e18; x[N+1] = L; vvec<ll> dp(N+2,vec<ll>(V+1,inf)); dp[0][V] = 0; for(int i=1;i<=N+1;i++) for(int j=0;j<=V;j++){ int d = x[i]-x[i-1]; if(d<=j) chmin(dp[i][j-d],dp[i-1][j]); if(i!=1){ int nj = min(V,j+v[i-1]); if(d<=nj) chmin(dp[i][nj-d],dp[i-1][j]+w[i-1]); } } ll ans = inf; // for(int i=0;i<=N+1;i++) for(int j=0;j<=V;j++) cerr << dp[i][j] << (j!=V? " ":"\n"); for(int j=0;j<=V;j++) chmin(ans,dp[N+1][j]); cout << (ans!=inf? ans:-1) << "\n"; }