#include <bits/stdc++.h>
using namespace std;

int main()
{
    ios::sync_with_stdio(false); cin.tie(0);
    int N, C, V; cin >> N >> C >> V;
    vector<int> S(V), T(V), Y(V), M(V);
    for(int&x: S) cin >> x;
    for(int&x: T) cin >> x;
    for(int&x: Y) cin >> x;
    for(int&x: M) cin >> x;
    vector<vector<tuple<int, int, int>>>conn(N);
    for(int i=0;i<V;++i) conn[S[i]-1].emplace_back(T[i]-1, Y[i], M[i]);
    vector<vector<bool>> vis(C+1, vector<bool>(N));
    using T3 = tuple<int, int, int>;
    priority_queue<T3, vector<T3>, greater<T3>> Q;
    Q.emplace(0, C, 0);
    while(!Q.empty())
    {
        auto [d, c, v] = Q.top(); Q.pop();
        if(vis[c][v]) continue; else vis[c][v] = true;
        if(v == N-1){ cout << d << endl; return 0; }
        for(auto [u, cc, dd]: conn[v]) if(c >= cc) Q.emplace(d+dd, c-cc, u);
    }
    cout << -1 << endl;
}