priority-queue

来源： https://stackoverflow.com/questions/25590546/why-does-stdpriority-queue-use-max-heap-instead-of-min-heap

来源： https://stackoverflow.com/questions/33479938/priority-queue-with-custom-comparator-segmentation-fault-when-pushing-second-tim

来源： https://stackoverflow.com/questions/33479938/priority-queue-with-custom-comparator-segmentation-fault-when-pushing-second-tim

来源： https://stackoverflow.com/questions/26510041/c-priority-queue-does-not-sort

来源： https://stackoverflow.com/questions/34477311/c-data-structure-that-automatically-sort-objects-by-the-value-of-a-member

问题 Creating a heap takes O(n) time while inserting into a heap (or priority queue) takes O(log(n)) time. Taking n inputs and inserting them into the priority queue, what would be the time complexity of the operation? O(n) or O(n*log(n)). Also, the same result would hold in case of emptying the entire heap too (i.e. n deletions), right? 回答1: If you have an array of size n and you want to build a heap from all items at once, Floyd's algorithm can do it with O(n) complexity. See Building a heap.

问题 Creating a heap takes O(n) time while inserting into a heap (or priority queue) takes O(log(n)) time. Taking n inputs and inserting them into the priority queue, what would be the time complexity of the operation? O(n) or O(n*log(n)). Also, the same result would hold in case of emptying the entire heap too (i.e. n deletions), right? 回答1: If you have an array of size n and you want to build a heap from all items at once, Floyd's algorithm can do it with O(n) complexity. See Building a heap.

问题 I have the following question: If asked whether to use a shift vs a multiply or divide for example the answer would be, let the JVM optimize. Example here: is-shifting-bits-faster-than-multiplying Now I was looking at the jdk source, for example Priority Queue and the code uses only shifting for both multiplication and division (signed and unsigned). Taking for granted that the post in SO is the valid answer I was wondering why in jdk they prefer to do it by shifting? Is it some subtle detail

问题 It's difficult to tell what is being asked here. This question is ambiguous, vague, incomplete, overly broad, or rhetorical and cannot be reasonably answered in its current form. For help clarifying this question so that it can be reopened, visit the help center. Closed 7 years ago . I would like to find a node in my priority queue but I did not find a solution :( If you have a solution, I'm interested. Thx for help. 回答1: If you really need to search through a std::priority_queue and want to

问题 I am looking at implementing a priority queue with an added requirement, a find/search function which will tell whether an item is anywhere within the queue. So the functions will be: insert, del-min and find. I am unsure whether I should use a Heap or a Self-balancing binary search tree. It appears PQs are usually implemented with a Heap, but I am wondering if there is any advantage in using a binary search tree since I also need that find function. Furthermore, on average I'll be doing more