pythonintermediate10 minutes

Build a Function to Flatten a Nested List of Integers

Create a Python function that takes a nested list of integers and returns a flat list containing all the integers in their original order.

Challenge prompt

Write a function named flatten_list that accepts a single parameter: a list which can contain integers or other lists (which themselves may contain integers or other lists, and so on). Your function should return a new flat list containing all the integers from the nested structure in the same left-to-right order.

Guidance

• Use recursion to handle arbitrarily nested lists.
• Check the type of each element to decide if it’s an integer or a sublist.

Hints

• Use isinstance(element, list) to check if an element is a list.
• If an element is an integer, append it to the result list; if it's a list, recursively call flatten_list on it.

Starter code

def flatten_list(nested_list):
    # Your code here
    pass

Expected output

flatten_list([1, [2, [3, 4], 5], 6]) # returns [1, 2, 3, 4, 5, 6]

Core concepts

recursionlist manipulation

Challenge a Friend

Send this duel to someone else and see if they can solve it.