#include <bits/stdc++.h>
using namespace std;
#define INF 1e9
#define FOR(i,a,b) for(int i=a;i<b;i++)
#define rep(i,b) FOR(i,0,b)
#define int long long
int N,C,V;

int dp[51][310];
signed main(){
  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];

  memset(dp,0x3f,sizeof(dp));
  rep(i,310)dp[1][i]=0;

  for(int i=0;i<V;i++){
    for(int j=0;j<=C;j++){

      //道があるか
        if(j-Y[i]>=0){
            dp[T[i]][j]=min(dp[T[i]][j],dp[S[i]][j-Y[i]]+M[i]);
        }
    }
  }




  int ans=INF;
  rep(i,C+1)ans=min(ans,dp[N][i]);
  if(ans<1e9)cout<<ans<<endl;
  else cout<<-1<<endl;


  return 0;
}