Level 4Exercise #88

Compress consecutive statuses

Run-length encode consecutive equal statuses as (status, count) pairs.

What you’ll practice

This Level 4 exercise focuses on groupby 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.groupby.

Sample Test Cases

Example #1

Input:run_length(['ok','ok','fail','ok'])

Output:[('ok',2),('fail',1),('ok',1)]

Reference Solution

Reveal Reference Solution

def run_length(statuses: list[str]) -> list[tuple[str,int]]:
    from itertools import groupby
    return [(status, sum(1 for _ in group)) for status, group in groupby(statuses)]

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Compress consecutive statuses

What you’ll practice

Sample Test Cases

Further Reading

Reference Solution