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01. Create a list of integers from 1 to nE02. Access elements by positive and negative indexE03. Slice a list to get first and last three itemsE04. Append an item and extend a listE05. Insert and remove elements in a listE06. Find element index or return -1E07. Count occurrences of a value in a listE08. Reverse a list in-place and by slicingE09. Sort a list of numbers ascending and descendingE10. Convert between lists and tuplesE11. Interleave two lists element by elementM12. Flatten a single-level list of listsM13. Filter a list using a predicateM14. Map a function over a listM15. Rotate a list by k positionsM16. Get unique elements preserving orderM17. Partition a list by a conditionM18. Replace a sublist slice with another listM19. Group equal consecutive values into sublistsH20. Reconstruct a list from value-count tuplesH

Problem No 8

Reverse a list in-place and by slicing

Easy

≈ 8 minute session

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Summary

Return a reversed list either by creating a new reversed copy or by reversing the original list in-place.

Problem statement

Write a function reverse_list(lst, in_place=False). When in_place is False (the default), return a new list that is the reversed copy of lst using slicing. When in_place is True, reverse lst in-place and return the same list object (now reversed). The function should work for lists containing any types.

Task

Implement a function that can return a reversed copy of a list or reverse the list in-place based on a flag.

Examples

Slicing reversal (default)

Input

reverse_list([1, 2, 3])

Output

[3, 2, 1]

Explanation

Default behavior returns a new list reversed using slicing.

Input format

A list as the first argument and an optional boolean in_place flag.

Output format

A list that is the reversed version of the input list (either a new list or the original mutated list).

Constraints

Do not import external libraries. When in_place is True, mutate the provided list; when False, do not change the original list.

Samples

Sample input 0

reverse_list([1, 2, 3], True)

Sample output 0

[3, 2, 1]

Explanation 0

The original list is reversed in-place and returned.

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