#include<bits/stdc++.h>
namespace {
#pragma GCC diagnostic ignored "-Wunused-function"
#include<atcoder/all>
#pragma GCC diagnostic warning "-Wunused-function"
using namespace std;
using namespace atcoder;
#define rep(i,n) for(int i = 0; i < (int)(n); i++)
#define rrep(i,n) for(int i = (int)(n) - 1; i >= 0; i--)
#define all(x) begin(x), end(x)
#define rall(x) rbegin(x), rend(x)
template<class T> bool chmax(T& a, const T& b) { if (a < b) { a = b; return true; } else return false; }
template<class T> bool chmin(T& a, const T& b) { if (b < a) { a = b; return true; } else return false; }
using ll = long long;
using P = pair<int,int>;
using VI = vector<int>;
using VVI = vector<VI>;
using VL = vector<ll>;
using VVL = vector<VL>;

} int main() {
  ios::sync_with_stdio(false);
  cin.tie(0);
  int n;
  cin >> n;
  VL p(n);
  rep(i, n) cin >> p[i], p[i] *= 2;
  constexpr long long INF = 1002003004005006007;
  int s = n, t = n + 1;
  mf_graph<ll> g(t + 1);
  int m;
  cin >> m;
  rep(_, m) {
    int u, v;
    cin >> u >> v;
    g.add_edge(v - 1, u - 1, INF);
  }
  int k;
  cin >> k;
  rep(_, k) {
    int a, b, s;
    cin >> a >> b >> s;
    a--, b--;
    p[a] += s;
    p[b] += s;
    g.add_edge(a, b, s);
    g.add_edge(b, a, s);
  }
  ll ans = 0;
  rep(i, n) {
    if (p[i] > 0) {
      ans += p[i];
      g.add_edge(s, i, p[i]);
    } else {
      g.add_edge(i, t, -p[i]);
    }
  }
  ans -= g.flow(s, t);
  cout << ans / 2 << '\n';
}