#include<iostream>
#include<vector>
#include<algorithm>
#include<iomanip>
#include<queue>
#include<set>
#include<map>
using namespace std;
#define OVERLOAD_REP(_1, _2, _3, name, ...) name
#define REP1(i, n) for (auto i = std::decay_t<decltype(n)>{}; (i) != (n); ++(i))
#define REP2(i, l, r) for (auto i = (l); (i) != (r); ++(i))
#define rep(...) OVERLOAD_REP(__VA_ARGS__, REP2, REP1)(__VA_ARGS__)
#define REP(i, l, r) rep(i, l, r+1)
#define all(x) (x).begin(),(x).end()
#define rall(x) (x).rbegin(),(x).rend()
using ll = long long;
using ld = long double;
using P = pair<ll,ll>;
struct Edge {
  int to; ll y, m;
};
//using Graph = vector<vector<int> >;
using Graph = vector<vector<Edge> >;
//const ll INF = 2e18;
const int INF = 2e9;
template<class T> using vc = vector<T>;
template<class T> using vv = vector<vector<T> >;
template<class T> using vvv = vector<vector<vector<T> > >;
template<class T> using pq = priority_queue<T>;
template<class T> using pq_g = priority_queue<T, vc<T>, greater<T> >;
template<class T> istream& operator>>(istream& i, vc<T>& v) { rep(j, 0, v.size()) i>>v[j]; return i; }
template<class T> ostream& operator<<(ostream& o, vc<T>& v) { rep(j, 0, v.size()) o<<v[j]<<" "; return o; }
template<class T> bool chmin(T& a, T b) {
  if(a > b) {
      a = b;
      return true;
  }
  return false;
}
template<class T> bool chmax(T& a, T b) {
  if(a < b) {
      a = b;
      return true;
  }
  return false;
}

int main() {
  // 高速化
  ios::sync_with_stdio(false);
  cin.tie(nullptr);

  // 小数点の出力桁数を指定
  cout << fixed << setprecision(10);
  // メイン
  // ダイクストラ法?
  // dist[v][c] -> 頂点vにc円を持っている時にかかる時間
  int N, C, V;
  cin >> N >> C >> V;
  vc<int> S(V), T(V), Y(V), M(V);
  cin >> S >> T >> Y >> M;
  rep(i, 0, V) S[i]--, T[i]--;
  Graph G(N);
  rep(i, 0, V) {
    G[S[i]].push_back({T[i], Y[i], M[i]});
  }

  vv<ll> dist(N, vc<ll>(C+1, INF));
  dist[0][C] = 0;
  pq_g<pair<ll, P>> que;
  que.push({dist[0][C], P(0, C)});

  while(!que.empty()) {
    ll d = que.top().first; int v = que.top().second.first, c = que.top().second.second;
    que.pop();

    if(d > dist[v][c]) continue;
    
    for(Edge e : G[v]) {
      if(c < e.y) continue;
      if(chmin(dist[e.to][c-e.y], dist[v][c] + e.m)) {
        que.push({dist[e.to][c-e.y], P(e.to, c-e.y)});
      }
    }
  }

  ll ans = INF;
  REP(c, 0, C) ans = min(ans, dist[N-1][c]);
  if(ans == INF) cout << -1 << endl;
  else cout << ans << endl;

  return 0;
}