Question

What’s faster: inserting into a priority queue, or sorting retrospectively?

I am generating some items that I need to be sorted at the end. I was wondering, what is faster in terms of complexity: inserting them directly in a priority_queue or a similar data structure, or using a sort algorithm at end?

Answer 1

Inserting n items into a priority queue will have asymptotic complexity O(n log n) so in terms of complexity, it’s not more efficient than using sort once, at the end.

Whether it’s more efficient in practice really depends. You need to test. In fact, in practice, even continued insertion into a linear array (as in insertion sort, without building a heap) may be the most efficient, even though asymptotically it has worse runtime.