#include <bits/stdc++.h>
#define N 16003
using namespace std;
ifstream fin("asmax.in");
ofstream fout("asmax.out");

int n,v[N],dp[N],nr=INT_MIN;

vector<int> lista[N];

void citire()
{
    fin>>n;
    for(int i=1;i<=n;i++)
    {
        fin>>v[i];
        nr=max(nr,v[i]);
    }

    for(int i=1;i<n;i++)
    {
        int x,y;
        fin>>x>>y;
        lista[x].push_back(y);
        lista[y].push_back(x);
    }
}

void dfs(int node,int tata)
{
    for(auto x:lista[node])
        if(x!=tata)
            dfs(x,node);
    dp[node]=v[node];
    for(auto x:lista[node])
    {
        if(x==tata)
            continue;
        dp[node]+=dp[x];
    }
    dp[node]=max(dp[node],0);
}


int main()
{
    citire();
    dfs(1,1);
    if(dp[1]==0)
        fout<<nr;
    else
        fout<<dp[1];
    return 0;
}