#pragma GCC optimize("Ofast,no-stack-protector,unroll-loops,fast-math") #include using namespace std; typedef long long ll; #define pb(...) emplace_back(__VA_ARGS__) #define mp(a, b) make_pair(a, b) #define all(x) x.begin(), x.end() #define rall(x) x.rbegin(), x.rend() #define lscan(x) scanf("%I64d", &x) #define lprint(x) printf("%I64d", x) #define rep(i, n) for (ll i = 0; i < (n); i++) #define rep2(i, n) for (ll i = (ll)n - 1; i >= 0; i--) #define REP(i, l, r) for (ll i = l; i < (r); i++) #define REP2(i, l, r) for (ll i = (ll)r - 1; i >= (l); i--) #define siz(x) (ll) x.size() template using rque = priority_queue, greater>; template bool chmin(T &a, const T &b) { if (b < a) { a = b; return 1; } return 0; } template bool chmax(T &a, const T &b) { if (b > a) { a = b; return 1; } return 0; } template void print(vector a) { if (a.empty()) cout << '\n'; else { for (int i = 0; i < a.size(); i++) cout << a[i] << (i + 1 == a.size() ? '\n' : ' '); } } // __int128_t gcd(__int128_t a, __int128_t b) { // if (a == 0) // return b; // if (b == 0) // return a; // __int128_t cnt = a % b; // while (cnt != 0) { // a = b; // b = cnt; // cnt = a % b; // } // return b; // } long long extGCD(long long a, long long b, long long &x, long long &y) { if (b == 0) { x = 1; y = 0; return a; } long long d = extGCD(b, a % b, y, x); y -= a / b * x; return d; } struct UnionFind { vector data; int num; UnionFind(int sz) { data.assign(sz, -1); num = sz; } bool unite(int x, int y) { x = find(x), y = find(y); if (x == y) return (false); if (data[x] > data[y]) swap(x, y); data[x] += data[y]; data[y] = x; num--; return (true); } int find(int k) { if (data[k] < 0) return (k); return (data[k] = find(data[k])); } ll size(int k) { return (-data[find(k)]); } bool same(int x, int y) { return find(x) == find(y); } int operator[](int k) { return find(k); } }; template struct Mod_Int { int x; Mod_Int() : x(0) { } Mod_Int(long long y) : x(y >= 0 ? y % mod : (mod - (-y) % mod) % mod) { } static int get_mod() { return mod; } Mod_Int &operator+=(const Mod_Int &p) { if ((x += p.x) >= mod) x -= mod; return *this; } Mod_Int &operator-=(const Mod_Int &p) { if ((x += mod - p.x) >= mod) x -= mod; return *this; } Mod_Int &operator*=(const Mod_Int &p) { x = (int)(1LL * x * p.x % mod); return *this; } Mod_Int &operator/=(const Mod_Int &p) { *this *= p.inverse(); return *this; } Mod_Int &operator++() { return *this += Mod_Int(1); } Mod_Int operator++(int) { Mod_Int tmp = *this; ++*this; return tmp; } Mod_Int &operator--() { return *this -= Mod_Int(1); } Mod_Int operator--(int) { Mod_Int tmp = *this; --*this; return tmp; } Mod_Int operator-() const { return Mod_Int(-x); } Mod_Int operator+(const Mod_Int &p) const { return Mod_Int(*this) += p; } Mod_Int operator-(const Mod_Int &p) const { return Mod_Int(*this) -= p; } Mod_Int operator*(const Mod_Int &p) const { return Mod_Int(*this) *= p; } Mod_Int operator/(const Mod_Int &p) const { return Mod_Int(*this) /= p; } bool operator==(const Mod_Int &p) const { return x == p.x; } bool operator!=(const Mod_Int &p) const { return x != p.x; } Mod_Int inverse() const { assert(*this != Mod_Int(0)); return pow(mod - 2); } Mod_Int pow(long long k) const { Mod_Int now = *this, ret = 1; for (; k > 0; k >>= 1, now *= now) { if (k & 1) ret *= now; } return ret; } friend ostream &operator<<(ostream &os, const Mod_Int &p) { return os << p.x; } friend istream &operator>>(istream &is, Mod_Int &p) { long long a; is >> a; p = Mod_Int(a); return is; } }; ll mpow2(ll x, ll n, ll mod) { ll ans = 1; x %= mod; while (n != 0) { if (n & 1) ans = ans * x % mod; x = x * x % mod; n = n >> 1; } return ans; } ll modinv2(ll a, ll mod) { ll b = mod, u = 1, v = 0; while (b) { ll t = a / b; a -= t * b; swap(a, b); u -= t * v; swap(u, v); } u %= mod; if (u < 0) u += mod; return u; } // constexpr int mod = 1000000007; constexpr int mod = 998244353; // constexpr int mod = 31607; using mint = Mod_Int; mint mpow(mint x, ll n) { mint ans = 1; while (n != 0) { if (n & 1) ans *= x; x *= x; n = n >> 1; } return ans; } // ----- library ------- // ----- library ------- int main() { ios::sync_with_stdio(false); std::cin.tie(nullptr); cout << fixed << setprecision(15); int n; cin >> n; vector> li(n); int p; rep(i, n - 1) cin >> p, li[--p].pb(i + 1); mint ans = 1; function dfs = [&](int now, int par, int dep) { for (auto &e : li[now]) { if (e != par) { ans *= dep + 1; dfs(e, now, dep + 1); } } }; dfs(0, -1, 0); cout << ans << endl; }