#new
N=int(input())
if N==1:
    C=1
else:
    A=[int(i)for i in input().split()]
    A.sort()
    C=0
    if A[0]!=A[1]:
        C+=1
  #  print (C)
    for i in range(1,N-1):
        if A[i]!=A[i-1] and A[i]!=A[i+1]:
            C+=1
   #     print (A[i-1])
    #    print (A[i])
    if A[N-2]!=A[N-1]:
        C+=1
print(C)