#define _GLIBCXX_DEBUG
#include <bits/stdc++.h>
using namespace std;

#define rep(i, n) for (int i = 0; i < (int)(n); i++)
#define all(v) v.begin(), v.end()
#define vin(vec, n) rep (i, n) cin >> vec[i];
using ll = long long;
using vi = vector<int>;
using vvi = vector<vector<int>>;
using vc = vector<char>;
using vvc = vector<vector<char>>;
using pii = pair<int, int>;
const ll MOD = 998244353, MOD2 = 1000000007;
/************************************************************************************/
//何を問われているか - 

ll N; const ll MAX_N = 2e5;
vector<ll> A(MAX_N); vector<vector<ll>> tree(MAX_N);
map<pair<ll, ll>, ll> dict;

ll rec(ll prev, ll pos) {
  if (dict.count({prev, pos})) return dict[{prev, pos}];
  ll res = 0;
  for (ll next : tree[pos]) {
    if (next != prev) {
      res += A[pos] * rec(pos, next) % MOD;
    }
  }
  if (prev != -1) res += A[pos];
  return dict[{prev, pos}] = res % MOD;
}

int main() {
  cin >> N; rep (i, N) cin >> A[i];
  rep (i, N-1) {
    ll u, v; cin >> u >> v; --u; --v;
    tree[u].push_back(v); tree[v].push_back(u);
  }
  ll ans = 0;
  rep (i, N) {
    ans += rec(-1, i);
    ans %= MOD;
  }
  cout << ans * ((MOD + 1) / 2) % MOD << '\n';
}