text: # Valera the Horse is going to the party with friends. He has been following the fashion trends for a while,
  # and he knows that it is very popular to wear all horseshoes of different color. Valera has got four horseshoes
  # left from the last year, but maybe some of them have the same color. In this case he needs to go to the store and
  # buy some few more horseshoes, not to lose face in front of his stylish comrades.
  
  # Fortunately, the store sells horseshoes of all colors under the sun and Valera has enough money to buy any four of
  # them. However, in order to save the money, he would like to spend as little money as possible, so you need to help
  # Valera and determine what is the minimum number of horseshoes he needs to buy to wear four horseshoes of different
  # colors to a party.
  
  # Input
  # The first line contains four space-separated integers s1, s2, s3, s4 (1 ≤ s1, s2, s3, s4 ≤ 109) — the
  # colors of horseshoes Valera has.
  
  # Consider all possible colors indexed with integers.
  
  # Output
  # Print a single integer — the minimum number of horseshoes Valera needs to buy.
  
  # Examples
  # inputCopy
  #   1 7 3 3
  # outputCopy
  #   1
  # inputCopy
  #   7 7 7 7
  # outputCopy
  #   3
  
  
  shoes = input().split()
  print(len(shoes)-len(set(shoes)))
  