using System;
using System.Collections.Generic;
using System.Text;

public class Program
{
    public void Proc(){
        Reader.IsDebug = false;
        int matiCount = int.Parse(Reader.ReadLine());
        this.Money = int.Parse(Reader.ReadLine());
        int roadCount = int.Parse(Reader.ReadLine());
        int[] inpt = Reader.GetInt();
        for(int i=0; i<inpt.Length; i++) {
            Road r = new Road();
            r.From = inpt[i];
            RoadList.Add(r);
            if(!RoadDic.ContainsKey(r.From)) {
                RoadDic.Add(r.From, new List<Road>());
            }
            RoadDic[r.From].Add(r);
        }
        inpt = Reader.GetInt();
        for(int i=0; i<inpt.Length; i++) {
            RoadList[i].To = inpt[i];
        }
        inpt = Reader.GetInt();
        for(int i=0; i<inpt.Length; i++) {
            RoadList[i].Cost = inpt[i];
        }
        inpt = Reader.GetInt();
        for(int i=0; i<inpt.Length; i++) {
            RoadList[i].Time = inpt[i];
        }
        int ans = this.GetAns(1, matiCount, this.Money);
        Console.WriteLine(ans);
    }
    
    private Dictionary<int, List<Road>> RoadDic = new Dictionary<int, List<Road>>();
    private Dictionary<string, int> dic = new Dictionary<string, int>();
    private int GetAns(int fromMati, int ToMati, int remain) {
        string key = fromMati + "#" + ToMati + "#" + remain;
        if(dic.ContainsKey(key)) {
            return dic[key];
        }
        if(fromMati == ToMati) {
            return 0;
        }
        if(remain < 0) {
            return -1;
        }
        int ans = int.MaxValue;
        foreach(Road r in RoadDic[fromMati]) {
            if(r.Cost <= remain) {
                int subAns = this.GetAns(r.To, ToMati, remain - r.Cost);
                if(subAns >= 0) {
                    ans = Math.Min(ans, subAns + r.Time);
                }
            }
        }
        if(ans == int.MaxValue) {
            ans = -1;
        }
        dic.Add(key, ans);
        return ans;
    }
    
    private List<Road> RoadList = new List<Road>();
    public class Road {
        public int From;
        public int To;
        public int Cost;
        public int Time;
    }
    
    private int Money = 0;
    
    public static void Main(string[] args)
    {
        Program prg = new Program();
        prg.Proc();
    }
}

class Reader
{
    public static bool IsDebug = true;
    
    private static System.IO.StringReader sr;
    
    public static string ReadLine() {
        if(IsDebug) {
            if(sr == null) {
                sr = new System.IO.StringReader(initStr.Trim());
            }
            return sr.ReadLine();
        } else {
            return Console.ReadLine();
        }
    }
    
    public static int[] GetInt(char delimiter = ' ') {
        string[] inpt = ReadLine().Split(delimiter);
        int[] ret = new int[inpt.Length];
        for(int i=0; i<inpt.Length; i++) {
            ret[i] = int.Parse(inpt[i]);
        }
        return ret;
    }
    
    private static string initStr = @"





";
}