#include <bits/stdc++.h>
using namespace std;
const int MAXN = 3005;
int n, val[MAXN], tot = 0;
int par[MAXN], sz[MAXN];
pair<int, pair<int, int> > edge[MAXN];
int find(int x) { return x == par[x] ? x : par[x] = find(par[x]); }
void join(int x, int y) { par[find(x)] = find(y); }
int main() {
  ios::sync_with_stdio(0);
  cin >> n;
  for (int i = 0; i < n - 1; i++) {
    cin >> edge[i].second.first >> edge[i].second.second >> edge[i].first;
    edge[i].second.first--, edge[i].second.second--;
  }
  for (int i = 0; i < n; i++) {
    cin >> val[i];
    tot += val[i];
    par[i] = i;
    sz[i] = 1;
  }
  sort(edge, edge + n - 1);
  for (int i = 0; i < n - 1; i++) {
    int a = edge[i].second.first, b = edge[i].second.second;
    if (find(a) == find(b)) continue;
    sz[find(b)] += sz[find(a)];
    val[find(b)] += val[find(a)];
    join(a, b);
    if (sz[find(a)] + val[find(a)] > tot) {
      cout << edge[i].first << '\n';
      return 0;
    }
  }
  cout << "0\n";
}
