K Largest Elements

Question

## Problem

Return the `k` largest values from a list of `n` elements.

## Example
```
nums=[3,1,5,12,2,11], k=3 -> [12,11,5]
```

## Constraints
- 1 ≤ k ≤ n ≤ 10^5

## Approach
Min-heap of size k -> O(n log k), or quickselect -> O(n) average.