#include<iostream>
#include<string>
#define MAX 20000
#define max(x,y) (x>y?x:y)
using namespace std;
struct node{
    int v;
    node *next;
}*head[MAX],tree[MAX];
int ptr, n, t;
int dp[MAX][2], w[MAX];
bool visit[MAX];
void initial(){
    ptr = 1;
    memset(head, 0, sizeof(head));
    memset(visit, 0, sizeof(visit));
    memset(dp, 0, sizeof(dp));
}
void addEdge(int x, int y){
    tree[ptr].v = y; 
    tree[ptr].next = head[x];head[x] = &tree[ptr++];
    tree[ptr].v = x; 
    tree[ptr].next = head[y]; head[y] = &tree[ptr++];
}
void tree_DP(int v){
    if (visit[v])return;
    visit[v] = true;
    node *p = head[v];
    while (p){
        if (!visit[p->v]){
            tree_DP(p->v);
            dp[v][1] += dp[p->v][0];//如果选当前节点，就不选儿子节点
            dp[v][0] += max(dp[p->v][0], dp[p->v][1]);
        }
        p = p->next;
    }
    dp[v][1] += w[v];
}
int main()
{
    int u, v;
    while (cin >> n){
        initial();
        for (int i = 1; i <= n; i++){
            cin >> w[i];
        }
        while (cin >> u >> v){
            if (u + v == 0)break;
            addEdge(u, v);
        }
        tree_DP(1);
        cout << max(dp[1][0], dp[1][1]) << endl;
    }
    return 0;
}