#include <fstream>
#include <algorithm>
#include <vector>

using namespace std;

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

int s[16004],n;
vector <int>l[16004];
bool v[16004];

void dfs(int nod)
{
    v[nod]=1;
    for (int i=0;i<l[nod].size();i++)
    {
        int vec=l[nod][i];
        if (v[vec]==0)
        {
            dfs(vec);
            if(s[nod]+s[vec]>s[nod]) s[nod]+=s[vec];
        }
    }
}

int i,x,y,maxim;

int main()
{
    fin >> n;
    for (i=1;i<=n;i++) fin >> s[i];
    while (fin >> x >> y)
    {
        l[x].push_back(y);
        l[y].push_back(x);
    }
    dfs(1);
    maxim=-100000004;
    for (i=1;i<=n;i++) maxim=max(maxim,s[i]);
    fout << maxim;

    return 0;
}