#include <bits/stdc++.h>
using namespace std;
const int N = 6e3 + 10;
int r[N], fa[N];
vector<int>e[N];
int dp[N][2];
int n;

void dfs(int u){
    dp[u][1] = r[u];
    dp[u][0] = 0;

    for(int i = 0;i < e[u].size();i++){
        int v = e[u][i];
        dfs(v);
        dp[u][1] += dp[v][0];
        dp[u][0] += max(dp[v][1], dp[v][0]);
    }
}

int main()
{
    ios::sync_with_stdio(false);
    cin.tie(0);
    cout.tie(0);

    cin >> n;
    for(int i = 1;i <= n;i++)cin >> r[i];
    for(int i = 1;i < n;i++){
        int x, y;
        cin >> x >> y;
        e[y].push_back(x);
        fa[x] = y;
    }
    int t = 1;
    while(fa[t])t = fa[t];
    dfs(t);
    cout << max(dp[t][0], dp[t][1]) << endl;
    return 0;
}