R=range
J=lambda:list(map(int,input().split()))
N,*_=J()
A=[0]+J()
F=[0]*(N+1)
a=0
for i in R(1,N+1):
	for c in R(1,3):
		j=i
		while F[j]<c:F[j],j=c,A[j]
		a+=F[j]<2
print(a)