import sys
input = sys.stdin.readline

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

mod = 998244353
def non_rec_dfs(s, G):
    N = len(G)
    stack = [s]
    par = [-1] * N
    sz = [1] * N
    dp = [0] * N
    ans = 0
    while stack:
        u = stack.pop()
        if u >= 0:
            stack.append(~u)
            for v in G[u]:
                if v == par[u]:
                    continue
                par[v] = u
                stack.append(v)
        else:
            u = ~u
            s1, s2 = 0, 0
            for v in G[u]:
                if v == par[u]:
                    continue
                sz[u] += sz[v]
                dp[u] += dp[v] * A[u]
                dp[u] %= mod
                s1 += dp[v]
                s2 += dp[v] ** 2

            dp[u] += A[u]
            dp[u] %= mod
            ans += (s1 ** 2 - s2) // 2 * A[u]
            ans %= mod

    return (ans + sum(dp) - sum(A)) % mod

print(non_rec_dfs(0, G))