The k largest numbers in Java
Java interview exercise on Collections, difficulty 2 of 3. Solve it in the editor beside a worked example, or cold in Interview mode with the example hidden; the tests run the moment you do.
Write topK(nums, k) that returns the k largest numbers in descending order, keeping only k numbers in memory at a time: a min-heap (PriorityQueue) of size k whose smallest element is dropped whenever a bigger number arrives. If k is larger than the list, return everything sorted descending; k = 0 gives an empty list.
Each exercise pairs a worked example with a twin problem to solve in a real editor; the tests run the moment you do. Interview mode hides the example: solve it from memory, without the hint or the solution, and it counts as solved cold. Progress is saved in your browser, and in your account if you sign in.