//#define _GLIBCXX_DEBUG
#include <bits/stdc++.h>
#define rep(i, n) for(int i=0; i<n; ++i)
#define all(v) v.begin(), v.end()
#define rall(v) v.rbegin(), v.rend()
using namespace std;
using ll = int64_t;
using ld = long double;
using P = pair<ll, ll>;
using vs = vector<string>;
using vi = vector<ll>;
using vvi = vector<vi>;
template<class T> using PQ = priority_queue<T>;
template<class T> using PQG = priority_queue<T, vector<T>, greater<T> >;
const int INF = 0xccccccc;
const ll LINF = 922337203685477580LL;
template<typename T1, typename T2>
inline bool chmax(T1 &a, T2 b) {return a < b && (a = b, true);}
template<typename T1, typename T2>
inline bool chmin(T1 &a, T2 b) {return a > b && (a = b, true);}
template<typename T1, typename T2>
istream &operator>>(istream &is, pair<T1, T2> &p) { return is >> p.first >> p.second;}
template<typename T1, typename T2>
ostream &operator<<(ostream &os, const pair<T1, T2> &p) { return os << p.first << ' ' << p.second;}

#define N 100010

//head

int n;
ll a[N], b[N];
vi G[N];

P dfs(int i, int j) {
  ll use = 0, nuse = a[i];
  vi sa;
  for(int ne:G[i]) {
    if(ne == j) continue;
    auto u = dfs(ne, i);
    nuse += max(u.first, u.second);
    use += u.second;
    sa.emplace_back(b[ne]+u.first-u.second);
  }
  ll now = use;
  sort(rall(sa));
  for(ll x:sa) {
    now += x + b[i];
    chmax(use, now);
  }
  return P(use, nuse);
}

int main() {
  ios::sync_with_stdio(false);
  cin.tie(0);
  cin >> n;
  rep(i, n) cin >> a[i];
  rep(i, n) cin >> b[i];
  rep(i, n-1) {
    int u, v;
    cin >> u >> v;
    u--; v--;
    G[u].emplace_back(v);
    G[v].emplace_back(u);
  }
  P ans = dfs(0, -1);
  cout << max(ans.first, ans.second) << endl;
}