


from __future__ import annotations

import re






def 	a__ (							A__							):

			def alphanum_key(A__							):
						return [int(A__							) if s.isdigit() else s.lower() for s in re.split('([0-9]+)',			A__							)]

			return sorted(A__,			key=A__							)


if __name__ == "__main__":
				import doctest

				doctest.testmod()







from collections import Counter






def 	a__ (							A__							):
			return sum(socks_by_color // 2 for socks_by_color in Counter(A__							).values()							)


if __name__ == "__main__":
				import doctest

				doctest.testmod()

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





