#include <iostream>
#include <vector>
#include <algorithm>
#include <atcoder/modint>
using namespace std;
using i64 = long long;
using u64 = unsigned long long;
using m32 = atcoder::static_modint<998244353>;
#define rep(i,n) for(int i=0; i<(int)(n); i++)


int main(){
    int N; cin >> N;
    vector<int> P(N, -1);
    for(int i=1; i<N; i++){ int p; cin >> p; P[i] = p-1; }
    vector<int> D(N, 0);
    for(int i=1; i<N; i++) D[i] = D[P[i]] + 1;
    m32 ans = 1;
    for(auto a : D) if(a >= 2) ans *= 2;
    cout << ans.val() << '\n';
    return 0;
}


struct ios_do_not_sync{
    ios_do_not_sync(){
        std::ios::sync_with_stdio(false);
        std::cin.tie(nullptr);
    }
} ios_do_not_sync_instance;