from sys import stdin,setrecursionlimit#,set_int_max_str_digits
#import pypyjit
#pypyjit.set_param('max_unroll_recursion=-1')
setrecursionlimit(20000000) # これこどふぉだと無理
#set_int_max_str_digits(200010)
mod = 998244353 
ii = lambda :int(stdin.readline())
mi = lambda :map(int,stdin.readline().split())
li = lambda :list(mi())
gmi = lambda :map(lambda x: int(x) - 1, stdin.readline().split())
gi = lambda :list(map(lambda x: 0 if x == "." else 1,input())) # グリッド入力受け取り
py = lambda :print("Yes")
pn = lambda :print("No")
pf = lambda :print("First") 
ps = lambda :print("Second")
vec = [(1,0),(-1,0),(0,-1),(0,1)]
vec1 = [(1,0),(1,1),(0,1),(-1,1),(-1,0),(-1,-1),(0,-1),(1,-1)] #8方向
inf = 2*10**18

from collections import defaultdict 
n = ii() 
a = li() 

g = defaultdict(list)

for _ in range(n-1):
    u,v = gmi()
    g[u].append(v) 

ans = 0 
inv = pow(2,mod-2,mod)
def dfs(v,par):
    global ans 
    res = [] 
    for i in g[v]:
        if i == par:
            continue 
        res.append(dfs(i,v)) 

    # ans の更新
    tmp = 0 
    tmpp = 0
    for i in res:
        tmp += i 
        tmpp += i*i
        tmpp %= mod
        tmp %= mod

    ans += a[v]*(tmp+(tmp*tmp-tmpp)*inv)
    ans %= mod

    return a[v]*(tmp+1) % mod 

dfs(0,-1)

print(ans)