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

const int INF = 1<<29;

struct edge{
    int from;
    int to;
    int dist;
    int cost;
    edge(){} ~edge(){}
    edge(int a, int b, int c): to(a), dist(b), cost(c) {}
    bool operator <(const edge& r) const {
        return dist > r.dist;
    }
};

int N, C, V;
vector<edge> G(1500);
int d[51][301];

int main(){
    scanf("%d%d%d", &N, &C, &V);
    for(int x = 0; x < V; x++){
        scanf("%d", &G[x].from);
    }
    for(int x = 0; x < V; x++){
        scanf("%d", &G[x].to);
    }
    for(int x = 0; x < V; x++){
        scanf("%d", &G[x].cost);
    }
    for(int x = 0; x < V; x++){
        scanf("%d", &G[x].dist);
    }
    for(int x = 0; x <= N; x++){
        fill(d[x], d[x]+C+1, INF);
    }
    d[1][C] = 0;
    for(int x = 0; x < N; x++){
        bool updated = false;
        for(auto& e : G){
            for(int y = e.cost; y <= C; y++){
                if(d[e.from][y] + e.dist < d[e.to][y - e.cost]){
                    updated = true;
                    d[e.to][y - e.cost] = d[e.from][y] + e.dist;
                }
            }
        }
        if(!updated) break;
    }
    int res = INF;
    for(int x = 0; x <= C; x++){
        res = min(res, d[N][x]);
    }
    if(res < INF){
        printf("%d\n", res);
    }else{
        puts("-1");
    }
    return 0;
}