#ifndef HIDDEN_IN_VISUAL_STUDIO // 折りたたみ用 // 警告の抑制 #define _CRT_SECURE_NO_WARNINGS // ライブラリの読み込み #include using namespace std; // 型名の短縮 using ll = long long; // -2^63 ~ 2^63 = 9 * 10^18(int は -2^31 ~ 2^31 = 2 * 10^9) using pii = pair; using pll = pair; using pil = pair; using pli = pair; using vi = vector; using vvi = vector; using vvvi = vector; using vl = vector; using vvl = vector; using vvvl = vector; using vb = vector; using vvb = vector; using vvvb = vector; using vc = vector; using vvc = vector; using vvvc = vector; using vd = vector; using vvd = vector; using vvvd = vector; template using priority_queue_rev = priority_queue, greater>; using Graph = vvi; // 定数の定義 const double PI = acos(-1); const vi dx4 = { 1, 0, -1, 0 }; // 4 近傍(下,右,上,左) const vi dy4 = { 0, 1, 0, -1 }; const vi dx8 = { 1, 1, 0, -1, -1, -1, 0, 1 }; // 8 近傍 const vi dy8 = { 0, 1, 1, 1, 0, -1, -1, -1 }; const int INF = 1001001001; const ll INFL = 4004004004004004004LL; const double EPS = 1e-10; // 許容誤差に応じて調整 // 入出力高速化 struct fast_io { fast_io() { cin.tie(nullptr); ios::sync_with_stdio(false); cout << fixed << setprecision(15); } } fastIOtmp; // 汎用マクロの定義 #define all(a) (a).begin(), (a).end() #define sz(x) ((int)(x).size()) #define distance (int)distance #define Yes(b) {cout << ((b) ? "Yes\n" : "No\n");} #define rep(i, n) for(int i = 0, i##_len = int(n); i < i##_len; ++i) // 0 から n-1 まで昇順 #define repi(i, s, t) for(int i = int(s), i##_end = int(t); i <= i##_end; ++i) // s から t まで昇順 #define repir(i, s, t) for(int i = int(s), i##_end = int(t); i >= i##_end; --i) // s から t まで降順 #define repe(v, a) for(const auto& v : (a)) // a の全要素(変更不可能) #define repea(v, a) for(auto& v : (a)) // a の全要素(変更可能) #define repb(set, d) for(int set = 0; set < (1 << int(d)); ++set) // d ビット全探索(昇順) #define repp(a) sort(all(a)); for(bool a##_perm = true; a##_perm; a##_perm = next_permutation(all(a))) // a の順列全て(昇順) #define repit(it, a) for(auto it = (a).begin(); it != (a).end(); ++it) // イテレータを回す(昇順) #define repitr(it, a) for(auto it = (a).rbegin(); it != (a).rend(); ++it) // イテレータを回す(降順) #define smod(n, m) ((((n) % (m)) + (m)) % (m)) // 非負mod #define uniq(a) {sort(all(a)); (a).erase(unique(all(a)), (a).end());} // 重複除去 #define EXIT(a) {cout << (a) << endl; exit(0);} // 強制終了 // 汎用関数の定義 template inline ll pow(T n, int k) { ll v = 1; rep(i, k) v *= n; return v; } template inline bool chmax(T& M, const T& x) { if (M < x) { M = x; return true; } return false; } // 最大値を更新(更新されたら true を返す) template inline bool chmin(T& m, const T& x) { if (m > x) { m = x; return true; } return false; } // 最小値を更新(更新されたら true を返す) // 演算子オーバーロード template inline istream& operator>> (istream& is, pair& p) { is >> p.first >> p.second; return is; } template inline ostream& operator<< (ostream& os, const pair& p) { os << "(" << p.first << "," << p.second << ")"; return os; } template inline istream& operator>> (istream& is, tuple& t) { is >> get<0>(t) >> get<1>(t) >> get<2>(t); return is; } template inline ostream& operator<< (ostream& os, const tuple& t) { os << "(" << get<0>(t) << "," << get<1>(t) << "," << get<2>(t) << ")"; return os; } template inline istream& operator>> (istream& is, tuple& t) { is >> get<0>(t) >> get<1>(t) >> get<2>(t) >> get<3>(t); return is; } template inline ostream& operator<< (ostream& os, const tuple& t) { os << "(" << get<0>(t) << "," << get<1>(t) << "," << get<2>(t) << "," << get<3>(t) << ")"; return os; } template inline istream& operator>> (istream& is, vector& v) { repea(x, v) is >> x; return is; } template inline ostream& operator<< (ostream& os, const vector& v) { repe(x, v) os << x << " "; return os; } template inline ostream& operator<< (ostream& os, const list& v) { repe(x, v) os << x << " "; return os; } template inline ostream& operator<< (ostream& os, const set& s) { repe(x, s) os << x << " "; return os; } template inline ostream& operator<< (ostream& os, const set>& s) { repe(x, s) os << x << " "; return os; } template inline ostream& operator<< (ostream& os, const unordered_set& s) { repe(x, s) os << x << " "; return os; } template inline ostream& operator<< (ostream& os, const map& m) { repe(p, m) os << p << " "; return os; } template inline ostream& operator<< (ostream& os, const map>& m) { repe(p, m) os << p << " "; return os; } template inline ostream& operator<< (ostream& os, const unordered_map& m) { repe(p, m) os << p << " "; return os; } template inline ostream& operator<< (ostream& os, stack s) { while (!s.empty()) { os << s.top() << " "; s.pop(); } return os; } template inline ostream& operator<< (ostream& os, queue q) { while (!q.empty()) { os << q.front() << " "; q.pop(); } return os; } template inline ostream& operator<< (ostream& os, deque q) { while (!q.empty()) { os << q.front() << " "; q.pop_front(); } return os; } template inline ostream& operator<< (ostream& os, priority_queue q) { while (!q.empty()) { os << q.top() << " "; q.pop(); } return os; } template inline ostream& operator<< (ostream& os, priority_queue_rev q) { while (!q.empty()) { os << q.top() << " "; q.pop(); } return os; } template inline vector& operator--(vector& v) { repea(x, v) --x; return v; } template inline vector& operator++(vector& v) { repea(x, v) ++x; return v; } // 手元環境(Visual Studio) #ifdef _MSC_VER #define popcount (int)__popcnt // 全ビット中の 1 の個数 #define popcountll (int)__popcnt64 inline int lsb(unsigned int n) { unsigned long i; _BitScanForward(&i, n); return i; } // 最下位ビットの位置(0-indexed) inline int lsbll(unsigned long long n) { unsigned long i; _BitScanForward64(&i, n); return i; } inline int msb(unsigned int n) { unsigned long i; _BitScanReverse(&i, n); return i; } // 最上位ビットの位置(0-indexed) inline int msbll(unsigned long long n) { unsigned long i; _BitScanReverse64(&i, n); return i; } template T gcd(T a, T b) { return b ? gcd(b, a % b) : a; } #define input_from_file(f) ifstream _is(f); cin.rdbuf(_is.rdbuf()); #define output_to_file(f) ofstream _os(f); cout.rdbuf(_os.rdbuf()); // 提出用(gcc) #else #define popcount (int)__builtin_popcount #define popcountll (int)__builtin_popcountll #define lsb __builtin_ctz #define lsbll __builtin_ctzll #define msb(n) (31 - __builtin_clz(n)) #define msbll(n) (63 - __builtin_clzll(n)) #define gcd __gcd #define input_from_file(f) #define output_to_file(f) #endif // デバッグ出力用 #ifdef _MSC_VER #define dump(x) cerr << "\033[1;36m" << (x) << "\033[0m" << endl; #define dumps(x) cerr << "\033[1;36m" << (x) << "\033[0m "; #define dumpel(a) { int _i_ = -1; cerr << "\033[1;36m"; repe(x, a) {cerr << ++_i_ << ": " << x << endl;} cerr << "\n\033[0m"; } #else #define dump(x) #define dumps(x) #define dumpel(v) #endif #endif // 折りたたみ用 //-----------------AtCoder 専用----------------- #include using namespace atcoder; //using mint = modint1000000007; using mint = modint998244353; //using mint = modint; // mint::set_mod(m); istream& operator>> (istream& is, mint& x) { ll x_; is >> x_; x = x_; return is; } ostream& operator<< (ostream& os, const mint& x) { os << x.val(); return os; } using vm = vector; using vvm = vector; using vvvm = vector; //---------------------------------------------- //【木の入力】O(n) /* * 親を並べた入力を受け取り,n 頂点の木を構成する. * * n : グラフの頂点の数 * g : ここにグラフを構築して返す * directed : 有向グラフなら true * one_indexed : 入力が 1-indexed で与えられるなら true */ void read_tree(int n, Graph& g, bool directed = false, bool one_indexed = true) { // verify : https://atcoder.jp/contests/arc028/tasks/arc028_3 g = Graph(n); repi(i, 1, n - 1) { int p; cin >> p; if (one_indexed) p--; g[p].push_back(i); if (!directed) g[i].push_back(p); } } //【根付き木】 /* * Rooted_tree() : O(1) * 空で初期化する. * * Rooted_tree(Graph g, int r) : O(n) * 木 g を r を根とみなした根付き木として受け取る. */ struct Rooted_tree { // verify : https://onlinejudge.u-aizu.ac.jp/courses/lesson/1/ALDS1/all/ALDS1_7_A struct Node { int parent = -1; // 親(なければ -1) vi child; // 子(なければ空リスト) int depth = -1; // 深さ(根からのパスの長さ) int& dist = depth; // 深さを距離ともみなす(パスのコストを 1 とみなす) int weight = -1; // 重さ(部分木のもつ辺の数) int height = -1; // 高さ(最も遠い葉までの距離) // デバッグ出力 friend ostream& operator<<(ostream& os, const Node& v) { os << "(p:" << v.parent << ", c:[" << v.child << "], d:" << v.depth << ", w:" << v.weight << ", h:" << v.height << ")"; return os; } }; int n; // 頂点数 int r; // 根 vector v; // 頂点 // コンストラクタ(空で初期化,木と根で初期化) Rooted_tree() : n(0), r(-1) {} Rooted_tree(Graph& g, int r_) : n(sz(g)), r(r_), v(n) { // s : 注目ノード,p : s の親 function dfs = [&](int s, int p) { v[s].parent = p; v[s].child.clear(); v[s].weight = 0; v[s].height = 0; repe(t, g[s]) { if (t == p) continue; v[t].depth = v[s].depth + 1; dfs(t, s); v[s].child.push_back(t); v[s].weight += v[t].weight + 1; chmax(v[s].height, v[t].height + 1); } }; // 根 r を始点として再帰関数を呼び出す. v[r].depth = 0; dfs(r, -1); } // アクセス Node const& operator[](int i) const { return v[i]; } Node& operator[](int i) { return v[i]; } // 大きさ int size() const { return n; } // デバッグ出力 friend ostream& operator<<(ostream& os, const Rooted_tree& rt) { rep(i, rt.n) os << rt[i] << endl; return os; } }; int main() { // input_from_file("input.txt"); // output_to_file("output.txt"); int n; cin >> n; Graph g; read_tree(n, g); Rooted_tree rt(g, 0); mint res = 1; repi(i, 1, n - 1) { res *= rt[i].depth; } cout << res << endl; }