#include <algorithm>
#include <array>
#include <cstddef>
#include <cstdint>
#include <fstream>
#include <iostream>
#include <string>
#include <vector>

namespace {
using std::cin;
using std::cout;
using std::int64_t;
using std::size_t;

namespace base {
template <typename T, size_t... sizes>
struct NestedArray {};

template <typename T, size_t size, size_t... sizes>
struct NestedArray<T, size, sizes...> {
  using Type = std::array<typename NestedArray<T, sizes...>::Type, size>;
};

template <typename T>
struct NestedArray<T> {
  using Type = T;
};

template <typename T, size_t... sizes>
using Array = typename NestedArray<T, sizes...>::Type;

void OptimizeIO() {
  std::ios::sync_with_stdio(false);
  cin.tie(nullptr), cout.tie(nullptr);
}

void OptimizeIO(const std::string &input_file, const std::string &output_file) {
  static std::ifstream input_stream(input_file);
  static std::ofstream output_stream(output_file);
  cin.rdbuf(input_stream.rdbuf());
  cout.rdbuf(output_stream.rdbuf());
  cin.tie(nullptr), cout.tie(nullptr);
}
}  // namespace base

using base::Array;

const int kMod = 998244353, kInv2 = (kMod + 1) / 2;

namespace mod {
inline void Add(int &a, int b) {
  a += b;
  if (a >= kMod) a -= kMod;
}

inline int Sum(int a, int b) {
  a += b;
  if (a >= kMod) a -= kMod;
  return a;
}

inline void Sub(int &a, int b) {
  a -= b;
  if (a < 0) a += kMod;
}

inline int Diff(int a, int b) {
  a -= b;
  if (a < 0) a += kMod;
  return a;
}

inline void Mul(int &a, int b) { a = static_cast<int64_t>(a) * b % kMod; }

inline int Prod(int a, int b) { return static_cast<int64_t>(a) * b % kMod; }

int Pow(int a, int b) {
  int ans = 1, prod = a;

  while (b) {
    if (b & 1) Mul(ans, prod);
    Mul(prod, prod), b >>= 1;
  }

  return ans;
}

inline int Inv(int a) { return Pow(a, kMod - 2); }
}  // namespace mod

const int kMaxN = 3.0e5 + 5;
int n;
Array<int, kMaxN> f, sum_f, fa;
Array<int, kMaxN, 2> ch;
Array<bool, kMaxN> vis;
Array<std::vector<int>, kMaxN> edge;

struct Node {
  int val, id;
};

inline bool operator<(const Node &a, const Node &b) { return a.val < b.val; }

Array<Node, kMaxN> a;

struct Matrix {
  int a11, a13, a21, a23;
};

inline int Helper(int a, int b, int c) {
  return (static_cast<int64_t>(a) * b + c) % kMod;
}

inline Matrix operator*(const Matrix &a, const Matrix &b) {
  return {mod::Prod(a.a11, b.a11), Helper(a.a11, b.a13, a.a13),
          Helper(a.a21, b.a11, b.a21), Helper(a.a21, b.a13, b.a23 + a.a23)};
}

Array<Matrix, kMaxN> val, sum;

struct Info {
  int g, h;
};

inline Info operator+(const Info &a, Info b) {
  b.g = mod::Prod(b.g + 1, kInv2);
  return {mod::Prod(a.g, b.g), mod::Sum(a.h, b.h)};
}

inline Info operator-(const Info &a, Info b) {
  b.g = mod::Prod(b.g + 1, kInv2);
  if (a.g == 0 || b.g == 1) return {a.g, mod::Diff(a.h, b.h)};
  return {mod::Prod(a.g, mod::Inv(b.g)), mod::Diff(a.h, b.h)};
}

Matrix GenMatrix(const Info &info, bool f) {
  if (f) return {0, 0, 0, info.h};
  int half = mod::Prod(info.g, kInv2);
  return {half, half, half, mod::Sum(half, info.h)};
}

Info Retrodict(const Matrix &a, bool f) {
  if (f) return {0, a.a23};
  return {mod::Sum(a.a11, a.a11), mod::Diff(a.a23, a.a11)};
}

void Dfs(int u, int fa) {
  f[u] = 1;

  for (int v : edge[u]) {
    if (v == fa) continue;
    Dfs(v, u);
    mod::Mul(f[u], mod::Prod(f[v] + 1, kInv2));
    mod::Add(sum_f[u], sum_f[v]);
  }

  ::fa[u] = fa;
  sum[u] = val[u] = GenMatrix({f[u], sum_f[u]}, false);
  mod::Add(sum_f[u], f[u]);
}

inline bool IsRoot(int p) { return p != ch[fa[p]][0] && p != ch[fa[p]][1]; }

inline int Get(int p) { return p == ch[fa[p]][1]; }

inline void PushUp(int p) {
  int x = ch[p][0], y = ch[p][1];

  if (!x && !y) {
    sum[p] = val[p];
  } else if (!x) {
    sum[p] = val[p] * sum[y];
  } else if (!y) {
    sum[p] = sum[x] * val[p];
  } else {
    sum[p] = sum[x] * val[p] * sum[y];
  }
}

void Rotate(int p) {
  int q = fa[p], k = Get(p);
  if (!IsRoot(q)) ch[fa[q]][Get(q)] = p;
  fa[p] = fa[q];
  ch[q][k] = ch[p][k ^ 1], fa[ch[p][k ^ 1]] = q;
  ch[p][k ^ 1] = q, fa[q] = p;
  PushUp(q), PushUp(p);
}

void Splay(int p) {
  while (!IsRoot(p)) {
    int q = fa[p];
    if (!IsRoot(q)) Get(p) == Get(q) ? Rotate(q) : Rotate(p);
    Rotate(p);
  }
}

inline Info Query(const Matrix &a) {
  return {mod::Sum(a.a11, a.a13), mod::Sum(a.a21, a.a23)};
}

void Access(int p) {
  int q = 0;

  while (p) {
    Splay(p);
    Info info = Retrodict(val[p], vis[p]);
    if (ch[p][1]) info = info + Query(sum[ch[p][1]]);
    if (q) info = info - Query(sum[q]);
    val[p] = GenMatrix(info, vis[p]);
    ch[p][1] = q, PushUp(p);
    q = p, p = fa[p];
  }
}

void Modify(int p) {
  Access(p), Splay(p);
  vis[p] = true;
  Info info = Retrodict(val[p], false);
  val[p] = GenMatrix(info, true);
  PushUp(p);
}

int Main() {
  base::OptimizeIO();
  cin >> n;

  for (int i = 1; i <= n; i++) {
    cin >> a[i].val;
    a[i].id = i;
  }

  std::sort(a.begin() + 1, a.begin() + n + 1);

  for (int i = 1; i < n; i++) {
    int u, v;
    cin >> u >> v;
    edge[u].emplace_back(v), edge[v].emplace_back(u);
  }

  Dfs(1, 0);
  int ans = 0, p = 1;
  mod::Add(ans, mod::Prod(a[1].val, f[1] + sum_f[1]));
  // cout << f[1] << " " << sum_f[1] << "\n";

  while (p < n) {
    int i = p;
    while (i < n && a[i].val == a[p].val) Modify(a[i++].id);
    Access(1);
    Info res = Query(val[1]);
    // cout << res.g << " " << res.h << "\n";
    mod::Add(ans, mod::Prod(a[i].val - a[p].val, res.g + res.h));
    p = i;
  }

  mod::Mul(ans, mod::Pow(2, n - 2));
  cout << ans << "\n";
  return 0;
}
}  // namespace

int main() { return Main(); }