#include <bits/stdc++.h>
#include <atcoder/all>
#define rep(i,n) for(int (i)=0;(i)<(n);(i)++)
#define rep2(i,m,n) for(int (i)=(m);(i)<(n);(i)++)
#define rep2ll(i,m,n) for(ll (i)=(m);(i)<(n);(i)++)
#define ALL(obj) (obj).begin(), (obj).end()
#define rALL(obj) (obj).rbegin(), (obj).rend()
using namespace std;
using ll = long long;
using P = pair<ll,ll>;
using mint = atcoder::modint998244353;
using VL = vector<ll>;
using VVL = vector<VL>;
using VVVL = vector<VVL>;
using VM = vector<mint>;
using VVM = vector<VM>;
using VVVM = vector<VVM>;
using VD = vector<double>;
using VVD = vector<VD>;
using VVVD = vector<VVD>;
template<class T>bool chmax(T &a, const T &b) { if (a<b) { a=b; return 1; } return 0; }
template<class T>bool chmin(T &a, const T &b) { if (b<a) { a=b; return 1; } return 0; }


int main(){
    ios::sync_with_stdio(false);
    cin.tie(0);
    ll k, n, m; cin>>k>>n>>m;
    VL a(k); rep(i,k) cin>>a[i], a[i]--;
    VL b(n); rep(i,n) cin>>b[i];
    atcoder::mcf_graph<ll,ll> g(n+2);
    ll S = n, T = S + 1;
    rep(i,k) g.add_edge(S, a[i], 1, 0);
    rep(i,n) g.add_edge(i, T, b[i], 0);
    rep(i,m){
        ll u, v, d; cin>>u>>v>>d; u--,v--;
        g.add_edge(u, v, k, d);
        g.add_edge(v, u, k, d);
    }
    cout<<g.flow(S, T, k).second;

    return 0;
}