#include #include using namespace std; using namespace atcoder; istream &operator>>(istream &is, modint &a) { long long v; is >> v; a = v; return is; } ostream &operator<<(ostream &os, const modint &a) { return os << a.val(); } istream &operator>>(istream &is, modint998244353 &a) { long long v; is >> v; a = v; return is; } ostream &operator<<(ostream &os, const modint998244353 &a) { return os << a.val(); } istream &operator>>(istream &is, modint1000000007 &a) { long long v; is >> v; a = v; return is; } ostream &operator<<(ostream &os, const modint1000000007 &a) { return os << a.val(); } typedef long long ll; typedef vector> Graph; typedef pair pii; typedef pair pll; #define FOR(i,l,r) for (int i = l;i < (int)(r); i++) #define rep(i,n) for (int i = 0;i < (int)(n); i++) #define all(x) x.begin(), x.end() #define rall(x) x.rbegin(), x.rend() #define my_sort(x) sort(x.begin(), x.end()) #define my_max(x) *max_element(all(x)) #define my_min(x) *min_element(all(x)) template inline bool chmax(T& a, T b) { if (a < b) { a = b; return 1; } return 0; } template inline bool chmin(T& a, T b) { if (a > b) { a = b; return 1; } return 0; } const int INF = (1<<30) - 1; const ll LINF = (1LL<<62) - 1; const int MOD = 998244353; const int MOD2 = 1e9+7; const double PI = acos(-1); vector di = {1,0,-1,0}; vector dj = {0,1,0,-1}; #ifdef LOCAL # include # define debug(...) debug_print::multi_print(#__VA_ARGS__, __VA_ARGS__) #else # define debug(...) (static_cast(0)) #endif using mint = modint998244353; template struct RerootingDP { struct edge{ int from, to, idx, rev_idx; }; RerootingDP (int _n = 0) : n(_n) { es.resize(n);} void add_edge(int u, int v, int idx1, int idx2){ es[u].push_back({u,v,idx1,idx2}); es[v].push_back({v,u,idx2,idx1}); } V build(int v = 0){ root = v; vis.resize(n,0); outs.resize(n); return dfs(root); } vector reroot(){ reverse_edge.resize(n); reverse_edge[root] = e(); answers.resize(n); bfs(root); return answers; } private: int n, root; vector> es; vector vis; vector> outs; vector reverse_edge; vector answers; V dfs(int v){ vis[v]++; E val = e(); for (auto &p : es[v]){ if (vis[p.to] > 0 && p.to != es[v].back().to) swap(p,es[v].back()); if (vis[p.to] > 0) continue; E nval = put_edge(dfs(p.to),p.idx); outs[v].emplace_back(nval); val = merge(val,nval); } return put_vertex(val,v); } void bfs(int v){ int siz = outs[v].size(); vector lui(siz+1), rui(siz+1); lui[0] = e(), rui[siz] = e(); for (int i = 0; i < siz; i++) lui[i+1] = merge(lui[i],outs[v][i]); for (int i = siz-1; i >= 0; i--) rui[i] = merge(outs[v][i],rui[i+1]); for (int i = 0; i < siz; i++){ reverse_edge[es[v][i].to] = put_edge(put_vertex(merge(merge(lui[i],rui[i+1]),reverse_edge[v]),v),es[v][i].rev_idx); bfs(es[v][i].to); } answers[v] = put_vertex(merge(lui[siz],reverse_edge[v]), v); } }; // Education dp subtree // https://atcoder.jp/contests/dp/submissions/37662999 using T_monoid = mint; // E using T_DP = mint; // V mint A[202020]; T_monoid merge(T_monoid a, T_monoid b){ return a + b; } T_monoid e(){ return 0; } T_monoid put_edge(T_DP x, int i){ return x; } T_DP put_vertex(T_monoid x, int v){ return (x + 1) * A[v]; } // 参考 // https://trap.jp/post/1702/ // https://null-mn.hatenablog.com/entry/2020/04/14/124151 // fがput_edge, gがput_vertex // 辺の情報が必要なときはedge[i]を作る、また頂点の情報が必要な時はvertex[v]を作る int main(){ cin.tie(0); ios_base::sync_with_stdio(false); int N; cin >> N; rep(i, N) cin >> A[i]; RerootingDP g(N); rep(i, N - 1){ int U, V; cin >> U >> V; U--; V--; g.add_edge(U, V, i, i); } g.build(0); vector B = g.reroot(); mint ans = 0; rep(i, N) ans += B[i] - (mint)A[i]; cout << ans / (mint)2 << endl; }