



def      lowerCAmelCase__		(   lowerCamelCase_		:		list):





				'''simple docstring'''

				if len(lowerCamelCase_) <= 1:
								return [tuple(lowerCamelCase_)]

				lowerCAmelCase__					:    List[str]												=					[]

				def generate(lowerCamelCase_		:		int	,lowerCamelCase_		:		list):
								lowerCAmelCase__					:    int												=					[0] * n
								res.append(tuple(lowerCamelCase_))

								lowerCAmelCase__					:    int												=					0
								while i < n:
												if c[i] < i:
																if i % 2 == 0:
																				lowerCAmelCase__						,		lowerCAmelCase__					:    Optional[int]												=					arr[i], arr[0]
																else:
																				lowerCAmelCase__						,		lowerCAmelCase__					:    Optional[Any]												=					arr[i], arr[c[i]]
																res.append(tuple(lowerCamelCase_))
																c[i] += 1
																lowerCAmelCase__					:    int												=					0
												else:
																lowerCAmelCase__					:    List[str]												=					0
																i += 1

				generate(len(lowerCamelCase_)	,lowerCamelCase_)
				return res


if __name__ == "__main__":
							__snake_case    :		Any  =input('Enter numbers separated by a comma:\n').strip()
							__snake_case    :		Any  =[int(item) for item in user_input.split(',')]
							print(heaps(arr))






def      lowerCAmelCase__		(   lowerCamelCase_		:		int = 1000):





				'''simple docstring'''

				lowerCAmelCase__						,		lowerCAmelCase__					:    int												=					1, 1
				lowerCAmelCase__					:    Any												=					2
				while True:
								lowerCAmelCase__					:    Optional[Any]												=					0
								lowerCAmelCase__					:    Any												=					fa + fa
								lowerCAmelCase__						,		lowerCAmelCase__					:    Optional[Any]												=					fa, f
								index += 1
								for _ in str(lowerCamelCase_):
												i += 1
								if i == n:
												break
				return index


if __name__ == "__main__":
							print(solution(int(str(input()).strip())))

