R=range
J=lambda:list(map(int,input().split()))
N,*_=J()
P=[0]+J()
Q=[0]*(N+1)
S=Q[:]
for p in P:Q[p]=1
for i in R(1,N+1):S[(1-Q[i])*P[P[i]]]=1
print(sum(S[1:]))