#include <iostream>
#include <vector>

template <class Cost = int>
struct Edge {
    int src, dst;
    Cost cost;
    Edge(int src = -1, int dst = -1, Cost cost = 1)
        : src(src), dst(dst), cost(cost){};

    bool operator<(const Edge<Cost>& e) const { return this->cost < e.cost; }
    bool operator>(const Edge<Cost>& e) const { return this->cost > e.cost; }
};

template <class Cost = int>
struct Graph {
    std::vector<std::vector<Edge<Cost>>> graph;

    Graph(int n = 0) : graph(n) {}

    void span(bool direct, int src, int dst, Cost cost = 1) {
        graph[src].emplace_back(src, dst, cost);
        if (!direct) graph[dst].emplace_back(dst, src, cost);
    }

    int size() const { return graph.size(); }
    void clear() { graph.clear(); }
    void resize(int n) { graph.resize(n); }

    std::vector<Edge<Cost>>& operator[](int v) { return graph[v]; }
    std::vector<Edge<Cost>> operator[](int v) const { return graph[v]; }
};

using lint = long long;

void solve() {
    int n;
    std::cin >> n;

    std::vector<lint> xs(n), ys(n);
    for (auto& x : xs) std::cin >> x;
    for (auto& y : ys) std::cin >> y;

    Graph<> graph(n);
    for (int i = 0; i < n - 1; ++i) {
        int u, v;
        std::cin >> u >> v;
        graph.span(false, --u, --v);
    }

    auto dfs = [&](auto&& f, int v, int p)
        -> std::pair<lint, lint> {
        lint s0 = xs[v], s1 = 0;

        for (auto e : graph[v]) {
            int u = e.dst;
            if (u == p) continue;

            auto [t0, t1] = f(f, u, v);
            s0 += std::max(t0, t1);
            s1 += std::max(t0, t1 + ys[v] + ys[u]);
        }
        return std::make_pair(s0, s1);
    };

    auto [s0, s1] = dfs(dfs, 0, -1);
    std::cout << std::max(s0, s1) << "\n";
}

int main() {
    std::cin.tie(nullptr);
    std::ios::sync_with_stdio(false);

    solve();

    return 0;
}