import sys
input=lambda:sys.stdin.readline().rstrip()
def write(i,depth):
	if depth[i]!=-1:
		return
	write(par[i],depth)
	depth[i]=depth[par[i]]+1
mod=998244353
N=int(input())
par=[0]+[int(input())-1 for i in range(N-1)]
depth=[-1 for i in range(N)]
depth[0]=0
for i in range(1,N):
	write(i,depth)
ans=1
for i in depth:
	ans=(ans*i)%mod
print(ans)