#include<bits/stdc++.h>
using namespace std;
#include <unordered_set>
#include <random>
//#define int long long
#define REP(i,m,n) for(int i=(m);i<(n);i++)
#define rep(i,n) REP(i,0,n)
#define pb push_back
#define all(a) a.begin(),a.end()
#define rall(c) (c).rbegin(),(c).rend()
#define mp make_pair
#define endl '\n'
//#define vec vector<ll>
//#define mat vector<vector<ll> >
#define fi first
#define se second
#define double long double
typedef long long ll;
typedef unsigned long long ull;
typedef pair<ll,ll> pll;
//typedef long double ld;
typedef complex<double> Complex;
const ll INF=1e9+7;
const ll MOD=998244353;
const ll inf=INF*INF;
const ll mod=MOD;
const ll MAX=100010;
const double PI=acos(-1.0);
typedef vector<vector<ll> > mat;
typedef vector<ll> vec;
double pi=M_PI;

vector<vector<ll> >G(MAX);

ll dfs(ll i,ll d){
    ll res=1;
    for(auto e:G[i]){
        res=res*dfs(e,d+1)%mod;
    }
    if(d>0)res=res*d%mod;
    return res;
}

void solve(){
    ll n;cin>>n;
    rep(i,n-1){
        ll p;cin>>p;
        p--;
        G[p].pb(i+1);
    }
    ll ans=dfs(0,0);
    cout<<ans<<endl;
}

signed main(){
    cin.tie(0);
    ios::sync_with_stdio(false);
    solve();
}