How to preallocate(reserve) a priority_queue?

Question

How can I preallocate a std::priority_queue with a container of type std::vector?

std::priority_queue

        

Answer 1

Another solution might be to make your own class derived from std::priority_queue, such as:

class MyPQueue : public std::priority_queue>
{
public:
    MyPQueue(size_t reserve_size)
    {
        this->c.reserve(reserve_size);
    }
};

then, in the code, create a MyPQueue object in this way:

MyPQueue mpq(1024);

which object can be upcasted back to the base class whenether needed.

std::priority_queue>& pq = mpq;