n=int(input())
root=0
happy=[]
graph=[[] for _ in range(n)]
visited=[False for _ in range(n)]
for _ in range(n):
    happy.append((int(input())))
for _ in range(n-1):
    l, k = map(int,input().split())
    graph[k - 1].append(l - 1)
    visited[l - 1] = True
for i in range(n):
    if not visited[i]:
        root = i
# print(happy)
# print(graph)
# print(visited)
# print(root)
def dfs(x):
    attend = happy[x]
    not_attend = 0
    for y in graph[x]:
        y_attend, y_not_attend = dfs(y)
        not_attend += max(y_not_attend, y_attend)
        attend += y_not_attend
    return attend,not_attend
print(max(dfs(root)))