#include <fstream>
#include <vector>
#define inf 1005

using namespace std;

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

const int Nmax = 16005;

vector<int> A[Nmax];

int DFS (int nod, vector<int>&v, vector<int>&best, vector<bool>&viz)
{
    viz[nod] = 1;
    for (auto i = 0; i < A[nod].size(); i++)
    {
        int nod_curent = A[nod][i];
        if (viz[nod_curent])
            continue;

        int x = DFS(nod_curent, v, best, viz);
        if (x > 0)
            best[nod] = best[nod] + x;
    }

    return best[nod];
}

int main()
{
    int n, maxim = -inf;
    in >> n;

    vector<int> v(n + 1);
    vector<int> best(n + 1);
    vector<bool> viz(n + 1);

    for (int i = 1; i <= n; i++)
        in >> best[i];

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

        A[x].push_back(y);
        A[y].push_back(x);
    }

    DFS(1, v, best, viz);

    for (int i = 1; i <= n; i++)
        maxim = max(maxim, best[i]);

    out << maxim;
    return 0;
}