#include <bits/stdc++.h>
#define REP(i, n) for (int i = 0; (i) < (int)(n); ++(i))
#define REP3(i, m, n) for (int i = (m); (i) < (int)(n); ++(i))
#define REP_R(i, n) for (int i = (int)(n)-1; (i) >= 0; --(i))
#define REP3R(i, m, n) for (int i = (int)(n)-1; (i) >= (int)(m); --(i))
#define ALL(x) ::std::begin(x), ::std::end(x)
using namespace std;

int64_t solve(int n, const vector<int64_t>& a, const vector<int64_t>& b, const vector<vector<int> >& g) {
    auto go = [&](auto&& go, int x, int parent) -> pair<int64_t, int64_t> {
        int64_t use = a[x];
        int64_t ign = 0;
        for (int y : g[x]) if (y != parent) {
            auto [sub_use, sub_ign] = go(go, y, x);
            use += max(sub_use, sub_ign);
            ign += max(sub_use, sub_ign + b[x] + b[y]);
        }
        return {use, ign};
    };
    auto [use, ign] = go(go, 0, -1);
    return max(use, ign);
}

// generated by online-judge-template-generator v4.6.0 (https://github.com/online-judge-tools/template-generator)
int main() {
    std::ios::sync_with_stdio(false);
    std::cin.tie(nullptr);
    constexpr char endl = '\n';
    int N;
    cin >> N;
    vector<int64_t> a(N), b(N);
    REP (i, N) { cin >> a[i]; }
    REP (i, N) { cin >> b[i]; }
    vector<vector<int> > g(N);
    REP (i, N - 1) {
        int u, v; cin >> u >> v;
        -- u;
        -- v;
        g[u].push_back(v);
        g[v].push_back(u);
    }
    auto ans = solve(N, a, b, g);
    cout << ans << endl;
    return 0;
}