#include <bits/stdc++.h>
#include <atcoder/all>
using namespace std;
using ll = long long;
#define rep(i,n) for(int i=0;i<(int)(n);i++)
using mint = atcoder::modint998244353;

int main(){
	int k,n,m;
	cin>>k>>n>>m;
	vector<int> a(k),b(n);
	rep(i,k) cin>>a.at(i);
	rep(i,n) cin>>b.at(i);
	rep(i,k) a.at(i)--;
	vector<vector<ll>> g(n,vector<ll>(n,1e18));
	rep(lp,m){
		int u,v;
		ll d;
		cin>>u>>v>>d;
		u--; v--;
		g.at(u).at(v)=d;
		g.at(v).at(u)=d;
	}
	rep(i,n) g.at(i).at(i)=0;
	{
		rep(i,n) rep(j,n) rep(k,n){
			if(g.at(j).at(k)>g.at(j).at(i)+g.at(i).at(k)){
				g.at(j).at(k)=g.at(j).at(i)+g.at(i).at(k);
			}
		}
	}
	atcoder::mcf_graph<ll,ll> mcf(k+n+2);
	rep(i,k) rep(j,n){
		mcf.add_edge(i,k+j,1,g.at(a.at(i)).at(j));
	}
	rep(i,k) mcf.add_edge(k+n,i,1,0);
	rep(i,n) mcf.add_edge(k+i,k+n+1,b.at(i),0);
	auto[mx,cs]=mcf.flow(k+n,k+n+1,k);
	cout<<cs<<endl;
}