#include<fstream>
#include<vector>
#define NMAX 16005
#define oo -(1<<30)
using namespace std;
ifstream fin("asmax.in");
ofstream fout("asmax.out");

vector <int> G[NMAX];
int N,Suma[NMAX], TT[NMAX], Sol=oo;
bool used[NMAX];

void Read()
{
    fin>>N;
    for(int i=1;i<=N;++i)
        fin>>TT[i];
    for(int i=1;i<=N;++i) // <
    {
        int x,y;
        fin>>x>>y;
        G[x].push_back(y);
        G[y].push_back(x);
    }

}

void DFS(int node)
{
    used[node]=true;
    Suma[node]=TT[node];
    for(unsigned int i=0;i<G[node].size();i++)
    {
        int Vecin=G[node][i];
        if(!used[Vecin])
        {
            DFS(Vecin);
            Suma[node]=max(Suma[node],Suma[node]+Suma[Vecin]);
        }
    }
    Sol=max(Sol,Suma[node]);
}

int main()
{
    Read();
    DFS(1);
    fout<<Sol;
}