#include <iostream>
#include <fstream>
#include <vector>

using namespace std;

//ifstream fin("omegalul.in");
//ofstream fout("omegalul.out");

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

const int N = 16001;

int n;

vector <int> a[N], nod;
bool viz[N];
int d[N];

void cit()
{
    fin>>n;

    for (int i=1; i<=n; i++)
    {
        int k;
        fin>>k;

        nod.push_back(k);
    }

    for (int i=1; i<=n; i++)
    {
        int x, y;
        fin>>x>>y;

        a[x].push_back(y);
        a[y].push_back(x);
    }
}

void dfs(int x)
{
    viz[x] = true;

    d[x] += nod[x-1];

    for (int i=0; i < a[x].size(); i++)
    {
        int y = a[x][i];

        if (!viz[y])
        {
            dfs(y);

            if (d[y] > 0) d[x] += d[y];
        }
    }
}

int main()
{
    cit();

    dfs(1);

    int mx = -99999999;

    for (int i=1; i<=n; i++)
        if (d[i] > mx) mx = d[i];

    fout<<mx;

    return 0;
}









/*

#include <iostream>
#include <fstream>
#include <vector>

using namespace std;

//ifstream fin("omegalul.in");
//ofstream fout("omegalul.out");

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

const long N = 30010, INF = 2e9;
long t, n, m;

vector <long> a[N], nod;
long d[N];

void cit()
{
    fin>>n>>m;

        for (int i=1; i <= n; i++)
            d[i] = -INF;

        if (nod.size()) nod.clear();

        for (int i=1; i <= n; i++)
            a[i].clear();

        for (int i=0; i < n; i++)
        {
            int x;
            fin>>x;

            nod.push_back(x);
        }

        for (int i=0; i<m; i++)
        {
            int x, y;

            fin>>x>>y;

            a[x].push_back(y);
        }
}

int calcul(int x)
{
    if (d[x] != -INF) return d[x];

    //cout<<"XD ";

    d[x] = nod[x-1];

    //cout<<"FML "<<x<<" "<<d[x]<<" :( ";

    long lol = d[x];

    for (int i=0; i < a[x].size(); i++)
    {


        long y = a[x][i];

        //cout<<"??? "<<a[x].size()<<" ??? "<<y<<" ???";

        d[x] = max(d[x], lol + calcul(y));
    }

    //cout<<x<<" "<<nod[x-1]<<" "<<d[x]<<"\n";

    return d[x];
}



void dfs(int x, int sum)
{
    viz[x] = elem;

    sum += nod[x-1];

    if (sum > summax) summax = sum;

    //cout<<elem<<" "<<x<<" "<<sum<<" "<<summax<<" "<<sumsupreme<<"\n";

    int y;

    for (int i = 0; i < a[x][t].size(); i++)
    {
        y = a[x][i][t];

        if (viz[y] < elem) dfs(y, sum);
    }
}



int main()
{
    fin>>t;

    for (int j=1; j<=t; j++)
    {
        //cout<<"\n";

        cit();

        //for (int i=1; i<=n; i++)
        //    cout<<"Calcul de "<<i<<" = "<<calcul(i)<<"\n";

        for (int i = 1; i <= n; i++)
            calcul(i);

        long mx = -INF;

        for (int i = 1; i <= n; i++)
        {
            //cout<<i<<" "<<d[i]<<" ";

            if (d[i] > mx) mx = d[i];
        }

        fout<<mx<<"\n";

    }

    return 0;
}

*/