#include <bits/stdc++.h>

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

vector <int> mat[16100];
int n,v[16100],a,b,summax = -1000000000;
bool viz[16100];


void dfs(int nod)
{
    viz[nod] = true;
    for (int i = 0; i < mat[nod].size(); ++i)
    {
        int y = mat[nod][i];
        if (viz[y] == false)
            {dfs(y);
            if (v[y] > 0)
                v[nod] += v[y];}
    }
}
int main()
{
    in>>n;
    for (int i = 1; i <= n; ++i)
        in>>v[i];
    while (in>>a>>b)
    {
        mat[a].push_back(b);
        mat[b].push_back(a);
    }
    for (int i = 1;i <= n;++i)
          if (viz[i] == false)
              dfs(i);
    for (int i = 1;i <= n;++i)
         summax = max(summax,v[i]);
    out<<summax;
    return 0;
}