#include "bits/stdc++.h"
using namespace std;
#define print(x) cout<<x<<endl;
#define rep(i,a,b) for(int i=a;i<b;i++)
#define REP(i,a) for(int i=0;i<a;i++)
#define printall(n,array) for(int i=0;i<n;i++){cout<<array[i]<<" ";}cout<<endl;
typedef long long ll;
typedef pair<int, int> PI;
typedef pair<int, PI> V;
typedef vector<int> VE;
const ll mod = 1000000007; //10^9+7

int dp[52][302];
bool used[52][302];
int n,c,v;
int s[1502],t[1502],y[1502],m[1502];

int main(){
  cin>>n;
  cin>>c;
  cin>>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]; 
  REP(i,n+1)REP(j,c+1)dp[i][j]=mod;
  dp[1][c]=0;
  REP(i,n){
    REP(j,c+1){
      REP(k,v){
        if(dp[s[k]][j]==mod||s[k]!=i||j-y[k]<0)continue;
        dp[t[k]][j-y[k]]=min(dp[t[k]][j-y[k]],dp[i][j]+m[k]);
        //print(i<<" "<<j<<" "<<s[k]<<" "<<t[k]<<" "<<dp[t[k]][j-y[k]]);
      }
    }
  }
 int min_=mod;
 REP(i,c+1)min_=min(dp[n][i],min_);
 min_=min_==mod?-1:min_;
 print(min_);
}