#include <bits/stdc++.h>
#include <atcoder/all>
using namespace std;
using namespace atcoder;
//using mint = modint1000000007;
//const int mod = 1000000007;
using mint = modint998244353;
const int mod = 998244353;
//const int INF = 1e9;
//const long long LINF = 1e18;
#define rep(i, n) for (int i = 0; i < (n); ++i)
#define rep2(i,l,r)for(int i=(l);i<(r);++i)
#define rrep(i, n) for (int i = (n) - 1; i >= 0; --i)
#define rrep2(i,l,r)for(int i=(r) - 1;i>=(l);--i)
#define all(x) (x).begin(),(x).end()
#define allR(x) (x).rbegin(),(x).rend()
#define P pair<int,int>
template<typename A, typename B> inline bool chmax(A & a, const B & b) { if (a < b) { a = b; return true; } return false; }
template<typename A, typename B> inline bool chmin(A & a, const B & b) { if (a > b) { a = b; return true; } return false; }

int main() {
	ios::sync_with_stdio(false);
	cin.tie(nullptr);
	int n; cin >> n;
	vector<int>a(n);
	rep(i, n)cin >> a[i];
	vector to(n, vector<int>());
	rep(i, n - 1) {
		int u, v; cin >> u >> v;
		u--, v--;
		to[u].push_back(v);
		to[v].push_back(u);
	}
	mint ans = 0;
	mint inv2 = mint::raw(2).inv();
	auto dfs = [&](auto &&self, int v, int p = -1)->mint {
		mint val = 0;
		mint sum = 0;
		for (auto nv : to[v]) {
			if (p == nv)continue;
			auto m = self(self, nv, v);
			val -= m * m;
			sum += m;
		}
		val += sum * sum;
		val *= inv2;
		ans += (val + sum) * a[v];
		return (sum + 1)*a[v];
	};
	dfs(dfs, 0);
	cout << ans.val() << endl;
	return 0;
}