#include <bits/stdc++.h>
using namespace std;
int n;
pair<int, pair<int, int> > q[3333];
int p[3333], sz[3333], kol[3333];
int maxsz, sum = 0, bad = 0;
int get(int x) {
  if (p[x] == x) return x;
  return p[x] = get(p[x]);
}
void unite(int x, int y) {
  x = get(x);
  y = get(y);
  maxsz = max(maxsz, sz[x] + sz[y]);
  sz[x] += sz[y];
  kol[x] += kol[y];
  if (kol[x] > sum - sz[x]) bad = 1;
  p[y] = x;
}
int main() {
  cin >> n;
  for (int i = 0; i < n - 1; i++) {
    scanf("%d%d%d", &q[i].second.first, &q[i].second.second, &q[i].first);
    q[i].second.first--;
    q[i].second.second--;
  }
  sort(q, q + n - 1);
  int ans = 0;
  bad = 0;
  for (int i = 0; i < n; i++) {
    p[i] = i;
    scanf("%d", &sz[i]);
    kol[i] = 1;
    sum += sz[i];
  }
  for (int i = 0; i < n; i++)
    if (kol[i] > sum - sz[i]) bad = 1;
  if (bad == 0 && n > 1) ans = q[0].first;
  for (int i = 0; i < n - 1;) {
    int j = i;
    while (j < n && q[j].first == q[i].first) {
      unite(q[j].second.first, q[j].second.second);
      j++;
    }
    i = j;
    if (bad == 0 && i < n) ans = q[i].first;
    if (bad) break;
  }
  cout << ans << endl;
  return 0;
}
