import java.util.*;

public class Main {
    public static void main(String[] args) throws Exception {
        Scanner koko = new Scanner(System.in);
        int n = koko.nextInt();
        int c = koko.nextInt();
        int v = koko.nextInt();
        int[] s = new int[v];
        int[] t = new int[v];
        int[] y = new int[v];
        int[] m = new int[v];
        for(int i=0; i<v; i++){
            s[i]=koko.nextInt();
        }
        for(int i=0; i<v; i++){
            t[i]=koko.nextInt();
        }
        for(int i=0; i<v; i++){
            y[i]=koko.nextInt();
        }
        for(int i=0; i<v; i++){
            m[i]=koko.nextInt();
        }
        boolean[][] stop = new boolean[n+1][c+1];
        int[][] stoptime = new int[n+1][c+1];
        stop[1][0]=true;
        stoptime[1][0]=0;
        for(int i=2; i<n+1; i++){
            for(int j=0; j<v; j++){
                if(i==t[j]){
                    for(int cost=0; cost<c+1-y[j]; cost++){
                        if(stop[s[j]][cost]){
                            if(stop[i][cost+y[j]]){
                                stoptime[i][cost+y[j]]=Math.min(stoptime[i][cost+y[j]], stoptime[s[j]][cost]+m[j]);
                            }else{
                                stop[i][cost+y[j]]=true;
                                stoptime[i][cost+y[j]]=stoptime[s[j]][cost]+m[j];
                            }
                        }
                    }
                }
            }
        }
        boolean flag = false;
        int min = n*1000;
        for(int cost=0; cost<c+1; cost++){
            if(stop[n][cost]){
                flag = true;
                min=Math.min(min, stoptime[n][cost]);
            }
        }
        if(flag){
            System.out.println(min);
        }else{
            System.out.println(-1);
        }
    }
}