#include <bits/stdc++.h>
using namespace std;

int main() {
    ios::sync_with_stdio(0);
    cin.tie(0);
    int n;
    cin >> n;
    vector<int> r(n + 1);
    for (int i = 1; i <= n; i++) {
        cin >> r[i];
    }
    vector<vector<int>> g(n + 1);
    for (int i = 0; i < n - 1; i++) {
        int a, b;
        cin >> a >> b;
        g[a].push_back(b);
        g[b].push_back(a);
    }
    vector<long long> dp(n + 1, 0);
    vector<int> p(n + 1, -1);
    queue<int> q;
    q.push(1);
    p[1] = 0;
    dp[1] = r[1];
    long long wynik = 0;
    while (!q.empty()) {
        int v = q.front();
        q.pop();
        bool lisc = true;
        for (int u : g[v]) {
            if (u == p[v]) continue;
            lisc = false;
            p[u] = v;
            dp[u] = dp[v] + r[u];
            q.push(u);
        }
        if (lisc) {
            wynik = max(wynik, dp[v]);
        }
    }
    cout << wynik;
}