#include <stdio.h>
#include <cstdio>
#include <iostream>
#include <iomanip>
#include <queue>
#include <set>
#include <vector>
#include <string>
#include <cstring>
#include <algorithm>
#include <cmath>
#include <complex>

using ll = long long int;
using namespace std;

ll INFTY = 1e10;

int main(){

  // read problem
  ll N, C, V, tmp;
  vector<ll> S, T, Y, M;
  
  cin >> N >> C >> V;
  for(ll i = 0; i < V; i++){
    cin >> tmp;
    S.push_back(tmp-1);
  }
  for(ll i = 0; i < V; i++){
    cin >> tmp;
    T.push_back(tmp-1);
  }
  for(ll i = 0; i < V; i++){
    cin >> tmp;
    Y.push_back(tmp);
  }
  for(ll i = 0; i < V; i++){
    cin >> tmp;
    M.push_back(tmp);
  }

  // solve problem
  vector<vector<ll> > dp(N, vector<ll>(C+1));
  for(ll i = 0; i < N; i++){
    for(ll j = 0; j < C+1; j++){
      dp[i][j] = INFTY;
    }
  }
  for(ll j = 0; j < C+1; j++){
    dp[0][j] = 0;
  }

  ll update = 1;
  //cerr << "hoge" << endl;
  while(update == 1){
    // reset update
    update = 0;
    // udpate dp
    for(ll i = 0; i < V; i++){
      for(ll j = 0; j <= C - Y[i]; j++){
        if(dp[T[i]][j+Y[i]] > dp[S[i]][j] + M[i]){
          //std::cerr << i << "," << j << endl;
          update = 1;
          dp[T[i]][j+Y[i]] = dp[S[i]][j] + M[i];
        }
      }
    }

    //cerr << "hoge" << endl;
  }

  cerr << "Answer:" << endl;
  if(dp[N-1][C] < INFTY){
    cout << dp[N-1][C] << endl;
  }
  else{
    cout << -1 << endl;
  }
  
  return 0;
}