#include <iostream>
#include <fstream>

using namespace std;
ifstream in ("asmax.in");
ofstream out ("asmax.out");

const int N_max=16005;

int vf[2 * (N_max - 1)];
int urm[2 * (N_max - 1)];
int lst[N_max];
int nr;
int s[N_max];

bool viz[N_max];

int scor[N_max];

int sol,n;

void adauga(int x, int y)
{
    nr++;
    vf[nr] = y;
    urm[nr] = lst[x];
    lst[x] = nr;
}

void dfs(int x)
{
    int y, p;
    viz[x] = true;
    p = lst[x];
    while(p)
    {
        y = vf[p];
        if(!viz[y])
        {
            dfs(y);
            if(scor[y] > 0) scor[x] += scor[y];
        }
        p = urm[p];
    }
    scor[x]+= s[x];
}



int main()
{
    int x,y;
    in>>n;
    for (int i=1;i<=n;i++)
        in>>s[i];
    for(int i=1;i<=n;i++)
    {
        in>>x>>y;
        adauga(x,y);
        adauga(y,x);
    }
    dfs(1);
    sol=scor[1];
    for(int i=2;i<=n;i++)
        sol=max(sol,scor[i]);
    out<<sol;
    return 0;
}