#include <bits/stdc++.h>

using namespace std;

#define REP(i, n)   for(int i = 0; i < (n); i++)
#define REPS(i, n)  for(int i = 1; i <= (n); i++)
#define RREP(i, n)  for(int i = (n)-1; i >= 0; i--)
#define RREPS(i, n) for(int i = (n); i > 0; i--)
#define ALL(v) v.begin(), v.end()
#define RALL(v) v.rbegin(), v.rend()
#define mp make_pair
#define mt make_tuple
#define pb push_back

using ll  = long long;
using pi  = pair<int, int>;
using pl  = pair<ll, ll>;
using vi  = vector<int>;
using vll = vector<ll>;
using vs = vector<string>;

const int MOD = 1e9 + 7;
const int INF = 1e9 + 7;

template<class T> bool chmax(T &a, const T &b) { if(a < b) { a = b; return true; } return false; }
template<class T> bool chmin(T &a, const T &b) { if(a > b) { a = b; return true; } return false; }

int N, C, V;
vector<vector<pi>> G;

int idx = 0;
vi sorted;
vector<bool> visited;

void dfs(int n)
{
    visited[n] = true;
    REP(i, N)
    {
        pi p = G[n][i];
        if(p.first != INF && p.second != INF)
        {
            if(!visited[i])dfs(i);
        }
    }
    sorted[idx++] = n;
}

int main()
{
    cin.tie(0);
    ios::sync_with_stdio(false);
    cout << fixed << setprecision(10);
    
    cin >> N >> C >> V;
    vi S(V), T(V), Y(V), M(V);
    REP(i, V) cin >> S[i], S[i]--;
    REP(i, V) cin >> T[i], T[i]--;
    REP(i, V) cin >> Y[i];
    REP(i, V) cin >> M[i];
    G.resize(N, vector<pi>(N, mp(INF, INF)));
    REP(i, V)
    {
        G[S[i]][T[i]] = mp(Y[i], M[i]);
    }

    // トポロジカルソート
    sorted.resize(N);
    visited.resize(N, false);
    dfs(0);
    reverse(ALL(sorted));
    //REP(i, N) cout << sorted[i] << " ";
    //cout << endl;

    vector<vi> time(N, vi(C+1, INF));
    time[sorted[0]][C] = 0;
    REP(i, N)
    {
        int n = sorted[i]; 
        REP(j, N)
        {
            pi p = G[n][j];
            REP(c, C+1)
            {
                if(c >= p.first) chmin(time[j][c-p.first], time[n][c] + p.second);
            }
        }
    }

    int m = 0;
    REP(i, N) if(sorted[i] == N-1) m = i;
    int ans = INF;
    REP(c, C+1)
    {
        chmin(ans, time[m][c]);
    }
    if(ans >= INF) cout << -1 << endl;
    else cout << ans << endl;
}