#include <iostream>
#include <algorithm>
#include <vector>
#include <queue>
#include <stack>
#include <string>
#include <iomanip>
#include <map>
#include <set>
#include <cmath>
#include <cstdio>
using namespace std;
#define rep(i,n) for(int (i)=0;(i)<(n);(i)++)
#define FOR(i,m,n) for(int (i)=(m);(i)<(n);(i)++)
#define All(v) (v).begin(),(v).end()
typedef long long ll;

struct edge{
    int t,y,m;
};

using pii = pair<int,int>;

int main(){
    int N,C,V;
    cin >> N >> C >> V;
    vector<int> S(V),T(V),Y(V),M(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];
    
    vector<vector<edge> >G(N);

    rep(i,V){
        G[S[i]-1].push_back({T[i]-1,Y[i],M[i]});
    }
    const int INF =1<<30;
    priority_queue<pii,vector<pii>,greater<pii> > que;
    vector<pii> d(N,make_pair(INF,0));//d:=(time,cost)
    d[0]=make_pair(0,0);
    que.push(make_pair(0,0));

    while(!que.empty()){
        pii p = que.top();que.pop();
        int v = p.second;
        if(d[v].first<p.first)continue;
        for(edge e:G[v]){
            if(d[e.t].first<d[v].first+e.m||d[v].second+e.y>C)continue;
            d[e.t].first=d[v].first+e.m;
            d[e.t].second=d[v].second+e.y;
            que.push(make_pair(d[e.t].first,e.t));
        }
    }

    if(d[N-1].first==INF)cout << -1 << endl;
    else cout << d[N-1].first << endl;
    return 0;
}