




from collections import Counter


def   A		(__A  :       list[int]			)  -> int:







     """simple docstring"""


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


if __name__ == "__main__":
    import doctest

    doctest.testmod()

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












def   A		(__A  :       int			)  -> int:







     """simple docstring"""


     if not isinstance(__A  ,							__A			):
          UpperCAmelCase_		=				F"""Input value of [number={number}] must be an integer"""
          raise TypeError(__A			)
     if number < 1:
          raise ValueError('''Input must be a positive integer'''			)
     return number * (2 * number - 1)


if __name__ == "__main__":
    import doctest

    doctest.testmod()






