




def  a_		(							__snake_case					)	->			int:

			'''simple docstring'''


			if not isinstance(__snake_case     ,		__snake_case					) or number < 0:
						raise ValueError('Input must be a non-negative integer'					)

			UpperCamelCase_     				= number & ~(number - 1)
			UpperCamelCase_     				= 0
			while intermediate:
						intermediate >>= 1
						index += 1
			return index - 1


if __name__ == "__main__":
				import doctest

				doctest.testmod(verbose=True)






from collections import Counter




def  a_		(							__snake_case					)	->			int:

			'''simple docstring'''


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


if __name__ == "__main__":
				import doctest

				doctest.testmod()

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