#include <bits/stdc++.h>
using namespace std;

const int nm=16005;

vector<vector<int>> v;
int ver[nm], dp[nm], val[nm], grad[nm];

void dfs(int x)
{
    ver[x]=1;
    for(auto i:v[x])
    {
        if(ver[i]==0)
        {
            dfs(i);
            if(dp[i]>0)
                dp[x]+=dp[i];
        }
    }
}

int main()
{
    ifstream cin("asmax.in");
    ofstream cout("asmax.out");
    int n, a, b, maxx=0;
    cin>>n;
    v.resize(n+1);
    for(int i=1; i<=n; i++)
        cin>>val[i];
    for(int i=1; i<n; i++)
    {
        cin>>a>>b;
        v[a].push_back(b);
        v[b].push_back(a);
        grad[a]++;
        grad[b]++;
    }
    for(int i=1; i<=n; i++)
    {
        if(grad[i]==1)
            dp[i]=val[i];
    }
    dfs(1);
    for(int i=1; i<=n; i++)
        maxx=max(maxx, dp[i]);
    cout<<maxx;
    return 0;
}