#include <fstream>
#include <vector>
using namespace std;

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

using VI = vector<int>;
using VVI = vector<VI>;
using VB = vector<bool>;

const int MaxN = 16001;
const int Inf = 0x3f3f3f3f;
int n, x ,y, maxim_s;
int val[MaxN], smax[MaxN];

VVI G;
VB V;

void ReadGraph();
void DFS_And_Calculate(int N);
void WriteSolution();

int main()
{
    ReadGraph();
    DFS_And_Calculate(1);
    WriteSolution();
    return 0;
}

void ReadGraph()
{
    fin >> n;
    for(int i = 1; i <= n; ++i)
        fin >> val[i];

    G = VVI(n + 1);
    V = VB(n + 1);

    while(fin >> x >> y)
    {
        G[x].push_back(y);
        G[y].push_back(x);
    }
}

void DFS_And_Calculate(int N)
{
    smax[N] = val[N];
    V[N] = true;
    for (const int& t : G[N])
    {
        if (V[t]) continue;
        DFS_And_Calculate(t);
        if (smax[t] > 0) smax[N] += smax[t];
    }
}

void WriteSolution()
{
    maxim_s = -Inf;
    for(int i = 1; i <= n; ++i)
        if (smax[i] > maxim_s) maxim_s = smax[i];
    fout << maxim_s;
}