#include <fstream>
#include <vector>

using namespace std;

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

int n, c[16005], x, y, dp[16005], maxim = -1e9;
vector<int> G[16005];
bool v[16005];
// dp[i] = suma maxima a subarborelui cu radacina "i"
// init: dp[1..n] = c[1..n];

void dfs(int nod) {
    v[nod] = true;
    for(auto i : G[nod]) {
        if(!v[i]) {
            dfs(i);
            dp[nod] = max(dp[nod], dp[i] + dp[nod]);
        }
    }
}

int main() {
    fin >> n;
    for(int i = 1; i <= n; i++) {
        fin >> c[i];
        dp[i] = c[i];
    }
    for(int i = 1; i < n; i++) {
        fin >> x >> y;
        G[x].push_back(y);
        G[y].push_back(x);
    }
    dfs(1);
    for(int i = 1; i <= n; i++) {
        maxim = max(maxim, dp[i]);
    }
    fout << maxim;
    return 0;
}