#include <bits/stdc++.h>
using namespace std;
using lint = long long;
using pi = array<lint, 2>;
#define sz(a) ((int)(a).size())
#define all(a) (a).begin(), (a).end()
const int MAXN = 300005;
const int mod = 998244353;
const int inv2 = (mod + 1) / 2;
// test weak... no line

struct mint {
	int val;
	mint() { val = 0; }
	mint(const lint &v) {
		val = (-mod <= v && v < mod) ? v : v % mod;
		if (val < 0)
			val += mod;
	}

	friend ostream &operator<<(ostream &os, const mint &a) { return os << a.val; }
	friend bool operator==(const mint &a, const mint &b) { return a.val == b.val; }
	friend bool operator!=(const mint &a, const mint &b) { return !(a == b); }
	friend bool operator<(const mint &a, const mint &b) { return a.val < b.val; }

	mint operator-() const { return mint(-val); }
	mint &operator+=(const mint &m) {
		if ((val += m.val) >= mod)
			val -= mod;
		return *this;
	}
	mint &operator-=(const mint &m) {
		if ((val -= m.val) < 0)
			val += mod;
		return *this;
	}
	mint &operator*=(const mint &m) {
		val = (lint)val * m.val % mod;
		return *this;
	}
	friend mint ipow(mint a, lint p) {
		mint ans = 1;
		for (; p; p /= 2, a *= a)
			if (p & 1)
				ans *= a;
		return ans;
	}
	mint inv() const { return ipow(*this, mod - 2); }
	mint &operator/=(const mint &m) { return (*this) *= m.inv(); }

	friend mint operator+(mint a, const mint &b) { return a += b; }
	friend mint operator-(mint a, const mint &b) { return a -= b; }
	friend mint operator*(mint a, const mint &b) { return a *= b; }
	friend mint operator/(mint a, const mint &b) { return a /= b; }
	operator int64_t() const { return val; }
};
mint ret = 0;

struct node {
	int j;
	mint A, S;
	bool operator<(const node &nd) const { return j < nd.j; }
};

vector<int> gph[MAXN];
int val[MAXN], sz[MAXN], n;

vector<node> merge(vector<node> a, vector<node> b) {
	vector<int> bisect(sz(a) + 1);
	int j = 0;
	for (int i = 0; i < sz(a); i++) {
		while (j < sz(b) && b[j].j < a[i].j)
			j++;
		bisect[i] = j;
	}
	bisect[sz(a)] = sz(b);
	mint tasum = 0, tssum = 0;
	mint asum = 0, ssum = 0;
	vector<node> c;
	for (int i = 0; i < sz(a); i++) {
		for (int j = (i ? bisect[i - 1] : 0); j < bisect[i]; j++) {
			asum += b[j].A;
			ssum += b[j].S;
		}
		tasum += a[i].A;
		tssum += a[i].S;
		a[i].A = a[i].A * ssum + a[i].S * asum;
		a[i].S = a[i].S * ssum;
		for (int j = bisect[i]; j < bisect[i + 1]; j++) {
			auto cp = b[j];
			cp.A = (tssum)*cp.A + tasum * cp.S;
			cp.S = (tssum)*cp.S;
			c.push_back(cp);
		}
	}
	vector<node> nxt(sz(a) + sz(c));
	merge(all(a), all(c), nxt.begin());
	vector<node> z;
	for (int i = 0; i < sz(nxt);) {
		int j = i;
		node toput;
		toput.j = nxt[i].j;
		while (j < sz(nxt) && nxt[i].j == nxt[j].j) {
			toput.A += nxt[j].A;
			toput.S += nxt[j].S;
			j++;
		}
		i = j;
		z.push_back(toput);
	}
	return z;
}

void pdfs(int x) {
	sz[x] = 1;
	for (auto &y : gph[x]) {
		gph[y].erase(find(all(gph[y]), x));
		pdfs(y);
		sz[x] += sz[y];
	}
	sort(all(gph[x]), [&](const int &p, const int &q) { return sz[p] > sz[q]; });
}
auto cmp = [](vector<node> &a, vector<node> &b) { return sz(a) > sz(b); };

vector<node> dnc(int s, int e, vector<vector<node>> &h) {
	if (s == e)
		return h[s];
	int m = (s + e) / 2;
	return merge(dnc(s, m, h), dnc(m + 1, e, h));
}
vector<node> solve(int x) {
	vector<int> hchn;
	for (int i = x;; i = gph[i][0]) {
		hchn.push_back(i);
		if (sz(gph[i]) == 0)
			break;
	}
	vector<vector<node>> heap;
	priority_queue<vector<node>, vector<vector<node>>, decltype(cmp)> pq(cmp); // max heap

	for (int i = 0; i < sz(hchn); i++) {
		int x = hchn[i];
		vector<node> a;
		a.push_back((node){val[x], mint(1), mint(1)});
		pq.push(a);
		for (int j = 1; j < sz(gph[x]); j++) {
			int y = gph[x][j];
			auto b = solve(y);
			for (auto &bb : b) {
				ret += mint(bb.j) * bb.A * mint((mod + 1) / 2);
				bb.A *= mint(inv2);
				bb.S *= mint(inv2);
			}
			b.push_back({val[x], mint(0), mint(inv2)});
			sort(all(b));
			pq.push(b);
		}
		while (sz(pq) > 1) {
			auto x = pq.top();
			pq.pop();
			auto y = pq.top();
			pq.pop();
			pq.push(merge(x, y));
		}
		heap.push_back(pq.top());
		pq.pop();
	}
	auto cur = heap.back();
	for (int i = sz(heap) - 2; i >= 0; i--) {
		for (auto &bb : cur) {
			ret += mint(bb.j) * bb.A * mint((mod + 1) / 2);
			bb.A *= mint(inv2);
			bb.S *= mint(inv2);
		}
		cur.push_back({val[hchn[i]], mint(0), mint(inv2)});
		sort(all(cur));
		cur = merge(heap[i], cur);
	}
	return cur;
}

int main() {
	ios_base::sync_with_stdio(0);
	cin.tie(0);
	cout.tie(0);
	cin >> n;
	for (int i = 0; i < n; i++) {
		cin >> val[i];
	}
	for (int i = 0; i < n - 1; i++) {
		int u, v;
		cin >> u >> v;
		u--;
		v--;
		gph[u].push_back(v);
		gph[v].push_back(u);
	}
	pdfs(0);
	auto ans = solve(0);
	for (auto &z : ans) {
		ret += z.A * mint(z.j);
	}
	cout << ret * ipow(mint(2), n - 1) << "\n";
}