Level 5Exercise #106

Merge sorted streams

Lazily merge already-sorted iterables into one sorted list.

What you’ll practice

This Level 5 exercise focuses on heapq.merge in the Algorithms curriculum. Solve the challenge prompt above using clear, idiomatic Python and the relevant language or standard-library tools.

Relevant Python reference: heapq — Heap queue algorithm.

Sample Test Cases

Example #1

Input:merge_streams([1,4,8], [2,3,9])

Output:[1,2,3,4,8,9]

Reference Solution

Reveal Reference Solution

def merge_streams(*streams) -> list[int]:
    import heapq
    return list(heapq.merge(*streams))

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Merge sorted streams

What you’ll practice

Sample Test Cases

Further Reading

Reference Solution