#include <fstream>
#include <vector>

using namespace std;

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

int sum = -9999999;
vector<int> adj[16001];
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);
            if (sum < sum + rez)
                sum += rez;
        }
    }
    return sum;
}

void citire_afisare(int n)
{
    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 - 1; i++)
    {
        fin >> x >> y;
        adj[x].push_back(y);
        adj[y].push_back(x);
    }

    int output = asmax(1, sum);
    fout << output;
}

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