delete element from priority queue in c++ stl

Question

Is i have a priority queue with declaration

priority_queue<<Node>,vector<Node>,myComp> openQ

i am inserting node objects into it. but at some time i have to delete the element from it. (not to remove the top element)

Currently to delete it i am popping the element and putting it in array. if the top most element is desired then expect it i push other elements in array.

This is like linear search and delete. I know its not efficient and i am looking for some better ways

Answer 1

priority_queue class is designed for using as queue with priorities. And it designed to remove elements with pop function. If you want to get different behavior you should use different class. For instance, std::map.

If you're ready to manually control a consistence of the queue you may take a look on std::make_heap. It's easy to create a max-heap with it. But in this case you need to manually rebuild a queue each time you want to remove an element.

Answer 2

std::set are orderd and can erase elements by value. the underlying datastructure is a binary search tree, thats why its cheaper to erase elements by value.

a priority queue would have to linearly search through the queue, so its possible but just not very efficient, thats why they didnt include it.