Level 4Exercise #93

Take while valid

Return the leading values that remain below a limit; stop at the first failure.

What you’ll practice

This Level 4 exercise focuses on takewhile in the Itertools curriculum. Solve the challenge prompt above using clear, idiomatic Python and the relevant language or standard-library tools.

Relevant Python reference: itertools.takewhile.

Sample Test Cases

Example #1

Input:leading_below([2,4,9,3], limit=8)

Output:[2,4]

Reference Solution

Reveal Reference Solution

def leading_below(values: list[int], limit: int) -> list[int]:
    from itertools import takewhile
    return list(takewhile(lambda value: value < limit, values))

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Take while valid

What you’ll practice

Sample Test Cases

Further Reading

Reference Solution