#include<bits/stdc++.h>
typedef uint64_t u64;
typedef int64_t i64;
using namespace std;

template<u64 mod> struct modint{
  u64 val;
  modint(i64 val_=0):val((val_%i64(mod)+i64(mod))%i64(mod)){}
  modint operator-(){
    return (val==0)?0:mod-val;
  }
  modint operator+(modint rhs){
    return modint(*this)+=rhs;
  }
  modint operator-(modint rhs){
    return modint(*this)-=rhs;
  }
  modint operator*(modint rhs){
    return modint(*this)*=rhs;
  }
  modint operator/(modint rhs){
    return modint(*this)/=rhs;
  }
  modint pow(i64 rhs){
    modint res=1,now=(*this);
    while(rhs){
      res*=((rhs&1)?now:1),now*=now,rhs>>=1;
    }
    return res;
  }
  modint &operator+=(modint rhs){
    val+=rhs.val,val-=((val>=mod)?mod:0);
    return (*this);
  }
  modint &operator-=(modint rhs){
    val+=((val<rhs.val)?mod:0),val-=rhs.val;
    return (*this);
  }
  modint &operator*=(modint rhs){
    val=val*rhs.val%mod;
    return (*this);
  }
  modint &operator/=(modint rhs){
    return (*this)*=rhs.pow(mod-2);
  }
  bool operator==(modint rhs){
    return val==rhs.val;
  }
  bool operator!=(modint rhs){
    return val!=rhs.val;
  }
  friend std::ostream &operator<<(std::ostream& os,modint x){
    return os<<(x.val);
  }
  friend std::istream &operator>>(std::istream& is,modint& x){
    u64 t;
    is>>t,x=t;
    return is;
  }
};

template<typename T> struct comb{
  vector<T> dat,idat;
  comb(int mx=3000000):dat(mx+1,1),idat(mx+1,1){
    for(int i=1;i<=mx;++i){
      dat[i]=dat[i-1]*i;
    }
    idat[mx]/=dat[mx];
    for(int i=mx;i>0;--i){
      idat[i-1]=idat[i]*i;
    }
  }
  T operator()(int n,int k){
    if(n<0||k<0||n<k){
      return 0;
    }
    return dat[n]*idat[k]*idat[n-k];
  }
};

constexpr u64 mod=998244353;
typedef modint<mod> mint;

void dfs(int v,int d,vector<vector<int>>& ch,mint& ans){
  ans*=max(1,d);
  for(auto& u:ch[v]){
    dfs(u,d+1,ch,ans);
  }
}

int main(){
  int N;
  cin>>N;
  vector<int> p(N,-1);
  vector<vector<int>> ch(N);
  for(int i=1;i<N;++i){
    cin>>p[i];
    p[i]--;
    ch[p[i]].emplace_back(i);
  }
  mint ans=1;
  dfs(0,0,ch,ans);
  cout<<ans<<endl;
}