#include <iostream>
#include <fstream>
#include <vector>
#include <climits>
#define MAX 16002
using namespace std;
int n,x,y,cost[MAX],s[MAX],vf[MAX],ans=INT_MIN;
vector<int> v[MAX];
/// s[i] = costul maxim al unui subarbore cu radacina in nodul i

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

void dfs(int nod){
    s[nod] = cost[nod];
    vf[nod] = 1;
    for(auto vecin: v[nod]){
        if(vf[vecin] == 0){
            dfs(vecin);
            if(s[nod]+s[vecin] > s[nod]){
                s[nod] += s[vecin];
            }
        }
    }
    ans = max(ans, s[nod]);
}

int main()
{
    fin >> n;
    for(int i = 1; i <= n; i++){
        fin >> cost[i];
    }
    for(int i = 1; i < n; i++){
        fin >> x >> y;
        v[x].push_back(y);
        v[y].push_back(x);
    }
    dfs(1);
    fout << ans;
    return 0;
}