#include <bits/stdc++.h>
#include <atcoder/modint>

using namespace std;
using ll = long long;
using namespace atcoder;
using mint = modint998244353;

int main(){
    cin.tie(nullptr);
    ios_base::sync_with_stdio(false);

    //dp(i)=iを根とする部分木での答え

    ll N, U, V;
    cin >> N;
    vector<ll> A(N);
    vector<vector<ll>> E(N);
    for (int i=0; i<N; i++) cin >> A[i];
    for (int i=0; i<N-1; i++){
        cin >> U >> V; U--; V--;
        E[U].push_back(V);
        E[V].push_back(U);
    }
    mint ans=0, iv=mint(2).inv();
    vector<mint> dp(N);
    auto dfs=[&](auto self, int from, int p=-1)->void{
        mint res=0, res2=0;
        for (auto to : E[from]){
            if (to == p) continue;
            self(self, to, from);
            res += dp[to];
            res2 += dp[to] * dp[to];
            dp[from] += dp[to];
        }
        dp[from] += 1;
        //fromをLCPとする頂点間での答えへの寄与
        //prod(i, j)dp[i]dp[j] * A[i]
        ans += (res*res-res2) * iv * A[from];
        dp[from] *= A[from];
        //fromを末端とするパスの答えへの寄与
        ans += dp[from]-A[from];
    };
    dfs(dfs, 0);
    cout << ans.val() << endl;

    return 0;
}