Level 4Exercise #98

Apply a boolean mask

Select data items whose corresponding selector is truthy.

What you’ll practice

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

Relevant Python reference: re — Regular expression operations, itertools.compress.

Sample Test Cases

Example #1

Input:select(['a','b','c'], [True,False,True])

Output:['a','c']

Reference Solution

Reveal Reference Solution

def select(data: list, mask: list[bool]) -> list:
    from itertools import compress
    return list(compress(data, mask))

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Apply a boolean mask

What you’ll practice

Sample Test Cases

Further Reading

Reference Solution