#include <fstream>
#include <iostream>
#include <stack>
#include <bitset>
#include <unordered_map>
#include <vector>
using namespace std;

ifstream fin("asmax.in");
ofstream fout("asmax.out");
int dp[16005];
vector<int> L[16005];
bitset<16005> viz;
void dfs(int nod) {
    viz[nod]=1;
    for (auto it:L[nod]) {
        if (!viz[it]) {
            dfs(it);
            if (dp[it]>0)
                dp[nod]+=dp[it];
        }
    }
}
int main() {
    int n;
    fin>>n;
    for (int i=1; i<=n; i++)
        fin>>dp[i];
    int x,y;
    while (fin>>x>>y) {
        L[x].push_back(y);
        L[y].push_back(x);
    }
    dfs(1);
    int maxx=-2e9;
    for (int i=1; i<=n; i++)
        maxx=max(dp[i],maxx);
    fout<<maxx;
    return 0;
}