#include <iostream>
using namespace std;

int n, c, v;
int *s, *t, *y, *m;

int calc_time(int now, int cost, int time)
{
    int rt = -1;
    int tmp;

    if (now == n)
    {
        if (cost <= c)
            return time;
        else
            return -1;
    }
    else
    {
        for (int i = 0; i < v; i++)
        {
            if (s[i] == now)
            {
                tmp = calc_time(t[i], cost + y[i], time + m[i]);
                if (tmp >= 0 && (rt < 0 || rt > tmp))
                    rt = tmp;
            }
        }
        return rt;
    }
}
int main()
{

    cin >> n >> c >> v;
    s = new int[v];
    t = new int[v];
    y = new int[v];
    m = new int[v];

    for (int i = 0; i < v; i++)
        cin >> s[i];
    for (int i = 0; i < v; i++)
        cin >> t[i];
    for (int i = 0; i < v; i++)
        cin >> y[i];
    for (int i = 0; i < v; i++)
        cin >> m[i];

    cout << calc_time(1, 0, 0) << endl;

    return 0;
}