N=int(input())
A=list(map(int, input().split()))
D=[[] for i in range(N)]
for i in range(N-1):
  u,v=map(int, input().split())
  u-=1;v-=1
  D[u].append(v);D[v].append(u)

from collections import deque
d=deque()
V=[-1]*N
d.append(0);V[0]=1

C=[]
while d:
  now=d.popleft()
  C.append(now)
  for nex in D[now]:
    if V[nex]==-1:
      V[nex]=1
      d.append(nex)

mod=998244353
dp=[[0]*2 for i in range(N)]
for now in C[::-1]:
  p=0;q=1;r=0
  for nex in D[now]:
    d=dp[nex][0]
    p+=d;q*=d;r+=d**2
    q%=mod;r%=mod
  dp[now][0]=A[now]+A[now]*p
  dp[now][1]=(p**2-r)*pow(2,-1,mod)*A[now]
  dp[now][0]%=mod
  dp[now][1]%=mod
  
ans=0
for i in range(N):
  x,y=dp[i]
  ans+=x
  ans+=y 
  ans-=A[i]
  ans%=mod 
print(ans)