1 # include <iostream>
 2 # include <cstring>
 3 # include <cstdio>
 4 using namespace std;
 5 const int MAX = 6010;
 6 struct node
 7 {
 8     int is;
 9     int next;
10 };
11 node tree[MAX * 2];
12 int head[MAX];
13 int tol = 0;
14 
15 int dp[MAX][2];
16 int vis[MAX];
17 int val[MAX];
18 
19 void add(int a, int b)
20 {
21     tree[tol].is = b;
22     tree[tol].next = head[a];
23     head[a] = tol++;
24     
25     tree[tol].is = a;
26     tree[tol].next = head[b];
27     head[b] = tol++;
28 }
29 void dfs(int root)
30 {
31     if(vis[root])
32         return;
33     vis[root] = 1;
34     int tep = head[root];
35     dp[root][1] = val[root];
36     
37     while(tep != -1)
38     {
39         if(!vis[tree[tep].is])
40         {
41             dfs(tree[tep].is);
42             dp[root][0] += max(dp[tree[tep].is][0], dp[tree[tep].is][1]);
43             dp[root][1] += dp[tree[tep].is][0];
44         }
45         tep = tree[tep].next;
46     }
47 }
48 int main()
49 {
50     int n;
51     while(~scanf("%d", &n))
52     {
53         memset(head, -1, sizeof(head));
54         memset(dp, 0, sizeof(dp));
55         memset(vis, 0, sizeof(vis));
56         tol = 0;
57         for(int i = 0; i < MAX; i++)
58         {
59             tree[i].is = 0;
60             tree[i].next = -1;
61         }
62         for(int i = 1; i <= n; i++)
63             scanf("%d", &val[i]);
64         
65         int a, b;
66         
67         while(scanf("%d%d", &a, &b))
68         {
69             if(a == 0 && b == 0)
70                 break;
71             add(a, b);
72         }
73         dfs(1);
74         printf("%d\n", max(dp[1][1], dp[1][0]));
75     }
76     return 0;
77 }