#include <bits/stdc++.h>
using namespace std;
const int MAXN = 6000;
int n;
int r[MAXN + 5];
vector<int> e[MAXN + 5];
int f[MAXN + 5][2];
void dfs(int u, int fa)
{
    f[u][0] = 0;
    f[u][1] = r[u];
    for (int v : e[u])
    {
        if (v == fa)
            continue;
        dfs(v, u);
        f[u][0] += max(f[v][1], f[v][0]);
        f[u][1] += f[v][0];
    }
}
int main()
{
    ios::sync_with_stdio(false);
    cin.tie(0);
    cin >> n;
    for (int i = 1; i <= n; i++)
        cin >> r[i];
    for (int i = 1; i <= n - 1; i++)
    {
        int u, v;
        cin >> u >> v;
        e[u].push_back(v);
        e[v].push_back(u);
    }
    dfs(1, 0);
    cout << max(f[1][0], f[1][1]);
    return 0;
}