#include <cassert>
#include <iostream>
#include <vector>
#include <algorithm>
#include <utility>

#define FOR(i, a, b) for (int i = (a); i < (b); i++)
#define RFOR(i, a, b) for (int i = (b)-1; i >= (a); i--)
#define rep(i, n) for (int i = 0; i < (n); i++)
#define rep1(i, n) for (int i = 1; i <= (n); i++)
#define rrep(i, n) for (int i = (n)-1; i >= 0; i--)

#define pb push_back
#define mp make_pair
#define fst first
#define snd second
#define show(x) cout << #x << " = " << x << endl
#define chmin(x, y) x = min(x, y)
#define chmax(x, y) x = max(x, y)
#define pii pair<int, int>
#define vi vector<int>

using namespace std;
template <class S, class T>
ostream& operator<<(ostream& o, const pair<S, T>& p)
{
    return o << "(" << p.first << "," << p.second << ")";
}
template <class T>
ostream& operator<<(ostream& o, const vector<T>& vc)
{
    o << "sz = " << vc.size() << endl
      << "[";
    for (const T& v : vc)
        o << v << ",";
    o << "]";
    return o;
}
typedef long long ll;

#define NMAX 51
#define MAX 101

int N, C, V;
int S[MAX];
int T[MAX];
int Y[MAX];
int M[MAX];

vector<pii> data[NMAX];
struct edge {
    int to;
    int cost;
    int tim;
};
vector<edge> edges[NMAX];

void dfs(int start)
{
    for (const auto& i : edges[start]) {
        const int to = i.to;
        const int cost = i.cost;
        const int tim = i.tim;
        for (const auto& j : data[start]) {
            const int time = j.fst;
            const int money = j.snd;
            if (money >= cost) {
                data[to].pb(mp(time + tim, money - cost));
            }
        }
        dfs(to);
    }
}

int main()
{
    cin >> N >> C >> V;
    rep(i, V)
    {
        cin >> S[i];
    }
    rep(i, V)
    {
        cin >> T[i];
    }
    rep(i, V)
    {
        cin >> Y[i];
    }
    rep(i, V)
    {
        cin >> M[i];
    }
    rep(i, V)
    {
        edges[T[i] - 1].pb(edge{S[i] - 1, Y[i], M[i]});
    }
    data[N - 1].pb(mp(0, C));

    dfs(N - 1);
    sort(data[0].begin(), data[0].end());
    if (data[0].empty()) {
        cout << -1 << endl;
    } else {
        cout << data[0][0].fst << endl;
    }

    return 0;
}