/**
	author:  shobonvip
	created: 2024.10.25 21:32:13
**/

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

//* ATCODER
#include<atcoder/all>
using namespace atcoder;
typedef modint998244353 mint;
//*/

/* BOOST MULTIPRECISION
#include<boost/multiprecision/cpp_int.hpp>
using namespace boost::multiprecision;
//*/

typedef long long ll;

#define rep(i, s, n) for (int i = (int)(s); i < (int)(n); i++)
#define rrep(i, s, n) for (int i = (int)(n)-1; i >= (int)(s); i--)

template <typename T> bool chmin(T &a, const T &b) {
	if (a <= b) return false;
	a = b;
	return true;
}

template <typename T> bool chmax(T &a, const T &b) {
	if (a >= b) return false;
	a = b;
	return true;
}

template <typename T> T max(vector<T> &a){
	assert(!a.empty());
	T ret = a[0];
	for (int i=0; i<(int)a.size(); i++) chmax(ret, a[i]);
	return ret;
}

template <typename T> T min(vector<T> &a){
	assert(!a.empty());
	T ret = a[0];
	for (int i=0; i<(int)a.size(); i++) chmin(ret, a[i]);
	return ret;
}

template <typename T> T sum(vector<T> &a){
	T ret = 0;
	for (int i=0; i<(int)a.size(); i++) ret += a[i];
	return ret;
}

int main(){
	ios_base::sync_with_stdio(false);
	cin.tie(NULL);
	
	int n; cin >> n;
	vector<mint> a(n);
	rep(i,0,n){
		int x; cin >> x;
		a[i] = x;
	}
	vector ikeru(n, vector<int>(0));
	rep(i,0,n-1){
		int u, v; cin >> u >> v;
		u -= 1;
		v -= 1;
		ikeru[u].push_back(v);
		ikeru[v].push_back(u);
	}
	mint ans = 0;
	vector<mint> dp(n);
	auto dfs = [&](auto self, int i, int p) -> void {
		for (int j: ikeru[i]){
			if (j == p) continue;
			self(self, j, i);
			ans += dp[i] * dp[j];
			dp[i] += dp[j] * a[i];
			ans += dp[j] * a[i];
		}
		dp[i] += a[i];

	};
	dfs(dfs,0,-1);
	cout << ans.val() << '\n';
}