#include <vector>
#include <queue>
#include <deque>
#include <stack>
#include <algorithm>
#include <functional>
#include <iostream>
#include <cstdio>
#include <cmath>
#include <cstdlib>
#include <ctime>
#include <cctype>
#include <string>
#include <cstring>

using namespace std;

int memo[50][301];
int ygraph[50][50];
int mgraph[50][50];
int n, c;
int ans;

#define INF 1000000000

int rec(int i, int j, int k) {
  if (j < 0) return INF;
  if (i == n-1) {
    ans = min(k, ans);
    return ans;
  }
  if (memo[i][j] != INF) {
    if (memo[i][j] > k) {
      memo[i][j] = k;
    }else {
      return memo[i][j];
    }
  }
  //  cout << i << " " << j << " " << k << endl;

  int ret = INF;
  for (int p = i+1; p < n; p++) {
    if (!ygraph[i][p]) continue;
    ret = min(ret, rec(p, j-ygraph[i][p], k+mgraph[i][p]));
  }

  return memo[i][j]=ret;
}

int main() {
  for (int i = 0; i < 50; i++) {
    for (int j = 0; j <= 301; j++) {
      memo[i][j] = INF;
    }
  }
  cin >> n;
  cin >> c;
  int v;
  cin >> v;
  int s[v], t[v], y[v], m[v];
  memset(ygraph, 0, sizeof(ygraph));
  memset(mgraph, 0, sizeof(mgraph));
  for (int i = 0; i < v; i++) cin >> s[i];
  for (int i = 0; i < v; i++) cin >> t[i];
  for (int i = 0; i < v; i++) cin >> y[i];
  for (int i = 0; i < v; i++) cin >> m[i];

  for (int i = 0; i < v; i++) {
    ygraph[s[i]-1][t[i]-1] = y[i];
    mgraph[s[i]-1][t[i]-1] = m[i];
  }

  ans = INF;
  if (rec(0, c, 0) != INF) {
    cout << ans << endl;
  }else {
    cout << -1 << endl;
  }
}