#include<bits/stdc++.h>
using namespace std;
using Int=long long;
using Real=long double;
template<class T>inline bool chmin(T&A,T B){return(A>B?A=B,1:0);}
template<class T>inline bool chmax(T&A,T B){return(A<B?A=B,1:0);}
#define REP(i,n)for(int i=0;i<(n);++i)
#define REP1(i,n)for(int i=1;i<=(n);++i)
#define ALL(x)begin(x),end(x)
#define drop(x){cout<<x<<'\n';return;}
int N,M,K,A[2<<17];
vector<int>C[2<<17];
void sol()
{
	cin>>N>>M>>K;
	REP(i,N)
	{
		int c;cin>>c;
		C[--c].push_back(i);
	}
	Int ans=1e18;
	REP(i,M)cin>>A[i];
	REP(i,M)
	{
		int sk=0,mt=0;
		REP(j,size(C[i]))
		{
			while(sk<size(C[i])&&C[i][j]+K>C[i][sk])++sk;
			chmax(mt,sk-j);
		}
		chmin(ans,(Int)A[i]*(K-mt));
	}
	cout<<ans<<endl;
}
int main()
{
	ios::sync_with_stdio(false);
	cin.tie(nullptr);
	cout.tie(nullptr);
	cout<<fixed<<setprecision(16);
	int T=1;
	//cin>>T;
	while(T--)sol();
}