#include<iostream>
#include<vector>
#include<fstream>
#define maxn 100005

using namespace std;

ifstream f("asmax.in");
ofstream g("asmax.out");

vector <int> t[maxn];
int i,j,n,m,nod[maxn],valori[maxn],cost;

int max(int a,int b)
        {
        if(a>b)return a;
        else return b;
        }
int dfs(int k)
        {
        nod[k]=1;
        int cost=valori[k];
        for(int j=0;j<t[k].size();j++)
        if(nod[t[k][j]]==0)cost=max(max(dfs(t[k][j]),valori[t[k][j]]+cost),cost);
        return cost;
        nod[k]=0;
        }

int main()
{
f>>n;
for(i=1;i<=n;i++)f>>valori[i];

while(f>>i>>j)
        {
        t[i].push_back(j);
        t[j].push_back(i);
        }
int l;
cost=-1001;
for(i=1;i<=n;i++)if(nod[i]==0){l=dfs(i);if(cost<l)cost=l;}
g<<l;
g.close();
return 0;
}