#include <bits/stdc++.h>

using namespace std;

ifstream fin("asmax.in");
ofstream fout("asmax.out");
#define cin fin
#define cout fout

#define N 16005
int f[N], c[N], v[N], n, x, y, cost, pct, rez;
vector < vector < int > > g;

int dfs(int nod)
{
    f[nod] = 1;
    c[nod] = v[nod];
    for(auto t : g[nod])
    {
        if(f[t] == 0)
        {
            int rez = dfs(t);
            c[nod] = max(c[nod]+rez,c[nod]);
        }
    }
    return c[nod];
}

int main()
{
    cin >> n;
    g.resize(n+5);
    cost = -1000000;
    for(int i = 1 ; i <= n ; i++)
    {
        cin >> v[i];
        if(v[i] > cost)
        {
            cost = v[i];
            pct = i;
        }
    }
    for(int i = 1 ; i < n ; i++)
    {
        cin >> x >> y;
        g[x].push_back(y);
        g[y].push_back(x);
    }
    dfs(pct);
    for(int i = 1 ; i <= n ; i++)
    {
        rez = max(rez,c[i]);
    }
    cout << rez;
    return 0;
}