n=int(input())
p=[0]+list(map(int,input().split()))
d=[0]*(n+1)
for i in range(1,n+1):
  d[p[i]]=1
v=[0]*(n+1)
q=[i for i in range(1,n+1) if d[i]==0]
q=[p[s] for s in q if p[s]!=0]
q=[p[s] for s in q if p[s]!=0]
print(len(set(q)))