#include <fstream>
#include <vector>
using namespace std;

ifstream fin("asmax.in");
ofstream fout("asmax.out");

int sum;
// vector<int> adj[16001];
vector<vector<int> > adj;
vector<int> visited, vals;

int asmax(int nod, int &sum_max)
{
    int sum = vals[nod];
    visited[nod] = 1;

    // for (auto i : adj[nod])
    for (int i = 0; i < adj[nod].size(); ++i)
    {
        int vecin = adj[nod][i];
        if (visited[vecin] == 0)
        {
            int rez = asmax(vecin, sum_max);
            if (sum < sum + rez)
                sum += rez;
        }
    }

    if (sum > sum_max)
        sum_max = sum;
    return sum;
}

void citire_afisare(int n)
{
    adj.resize(n + 1);
    visited.resize(n + 1, 0);
    vals.resize(n + 1);

    for (int i = 1; i <= n; ++i)
        fin >> vals[i];

    int x, y;
    for (int i = 1; i < n; ++i)
    {

        fin >> x >> y;
        adj[x].push_back(y);
        adj[y].push_back(x);
    }

    sum = -999999;

    int output = asmax(1, sum);

    fout << output;
}

int main()
{
    int n;
    fin >> n;
    citire_afisare(n);
    return 0;
}