#include <algorithm>
#include <cstdio>
#include <cstdlib>
#include <cctype>
#include <cmath>
#include <iostream>
#include <queue>
#include <list>
#include <map>
#include <numeric>
#include <set>
#include <sstream>
#include <string>
#include <vector>
using namespace std;
#define REP(i,a,n) for(int i=(a); i<(int)(n); i++)
#define rep(i,n) REP(i,0,n)
#define FOR(it,c) for(__typeof((c).begin()) it=(c).begin(); it!=(c).end(); ++it)
#define ALLOF(c) (c).begin(), (c).end()
typedef long long ll;

#define INF 1000000000

vector<int> S, T, Y, M;

int solve(int N, int C){

  bool visited[N+1][C+1];
  int sec[N+1][C+1];
  rep(i,N+1){
    rep(j,C+1){
      sec[i][j] = INF;
      visited[i][j] = false;
    }
  }
  sec[1][0] = 0;

  while(true){
    int minpos, mincost, minsec = INF;
    REP(i,1,N+1){
      rep(j,C+1){
        if(minsec > sec[i][j] && !visited[i][j]){
          minpos = i;
          mincost = j;
          minsec = sec[i][j];
        }
      }
    }
    
    if(minsec == INF) break;
    if(minpos == N) return minsec;
    visited[minpos][mincost] = true;

    rep(i,Y.size()){
      int s = S[i];
      int t = T[i];
      int y = Y[i];
      int m = M[i];
      if(minpos != s) continue;
      if(mincost + y <= C &&
         sec[t][mincost+y] > minsec + m){
        sec[t][mincost+y] = minsec + m;
      }
    }
  }
  return -1;
}

int main(){
  int N, C, V, tmp;

  cin >> N >> C >> V;
  rep(i,V){
    cin >> tmp;
    S.push_back(tmp);
  }
  rep(i,V){
    cin >> tmp;
    T.push_back(tmp);
  }
  rep(i,V){
    cin >> tmp;
    Y.push_back(tmp);
  }
  rep(i,V){
    cin >> tmp;
    M.push_back(tmp);
  }
  
  cout << solve(N, C) << endl;

  return 0;
}