#include<iostream>
#include<set> 
#include<algorithm>
#include<vector>
#include<string>
#include<set>
#include<map>
#include<numeric>
#include<queue>
#include<cmath>
#include <unordered_set>
#include<cassert>
using namespace std;
typedef long long ll;
const ll INF=1LL<<60;
typedef pair<int,int> P;
typedef pair<int,P> PP;
const ll MOD=998244353;


int main(){
    int N;
    cin>>N;
    vector<vector<int>> G(N);
    vector<int> p(N);
    for(int i=1;i<N;i++){
        cin>>p[i];
        p[i]--;
        //G[i].push_back(p[i]);
        G[p[i]].push_back(i);
    }

    vector<int> depth(N,0);

    auto dfs=[&](auto f,int now,int d)->void{
        depth[now]=d;
        for(int to:G[now]){
            f(f,to,d+1);
        }
    };

    dfs(dfs,0,0);

    ll ans=1;
    for(int i=0;i<N;i++){
        ans*=max(1,depth[i]);
        ans%=MOD;
    }

    cout<<ans<<endl;

}