K Smallest Elements

Difficulty: Medium · Topic: Heaps

Given an array nums and an integer k, return the k smallest elements in ascending order. A heap of size k (or a partial selection) avoids fully sorting when k is small.

Examples

k_smallest([3,1,2,5,4], 2)
→ [1,2]

k_smallest([5], 1)
→ [5]

Target complexity: time O(n log k), space O(k)

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