



from collections import Counter


def 						UpperCAmelCase__   (   UpperCAmelCase__			:list[int]       ):






 '''simple docstring'''

 return sum(socks_by_color // 2 for socks_by_color in Counter(UpperCAmelCase__       ).values()       )


if __name__ == "__main__":
     import doctest

     doctest.testmod()

     A_		:  List[str]										=  [int(x) for x in input('''Enter socks by color :''').rstrip().split()]
     print(F"""sock_merchant({colors}) = {sock_merchant(colors)}""")






from collections import Counter


def 						UpperCAmelCase__   (   UpperCAmelCase__			:list[int]       ):






 '''simple docstring'''

 return sum(socks_by_color // 2 for socks_by_color in Counter(UpperCAmelCase__       ).values()       )


if __name__ == "__main__":
     import doctest

     doctest.testmod()

     A_		:  List[str]										=  [int(x) for x in input('''Enter socks by color :''').rstrip().split()]
     print(F"""sock_merchant({colors}) = {sock_merchant(colors)}""")

