#include <bits/stdc++.h>

using namespace std;
ifstream in("asmax.in");
ofstream out("asmax.out");
const int nmax=16e3;
int n;
int value[nmax+1], dp[nmax+1];
vector <int> graph[nmax+1];
bitset <nmax+1> vis;
void dfs(int start)
{
    if(vis[start]==0)
    {
        vis[start]=1;
        for(int i=0; i<graph[start].size(); i++)
        {
            int copil=graph[start][i];
            if(vis[copil]==0)
            {
                dfs(copil);
                dp[start]=max(dp[start], dp[start]+dp[copil]);
            }
        }
        dp[start]+=value[start];
    }
}
int main()
{
    in>>n;
    for(int i=1; i<=n; i++)
    {
        in>>value[i];
    }
    int x, y;
    for(int i=2; i<=n; i++)
    {
        in>>x>>y;
        graph[x].push_back(y);
        graph[y].push_back(x);
    }
    dfs(1);
    int rez=-1e9;
    for(int i=1; i<=n; i++)
    {
        rez=max(rez, dp[i]);
    }
    out<<rez;
}