A priority queue is not a new container; it is a templatized adapter class that wraps an existing container and provides high-level functionalities that are required for priority queue operations, while hiding the unnecessary functionalities that are irrelevant for a priority queue. A priority queue makes use of a vector container by default; however, a deque container also meets the requirement of the priority queue. Hence, during the priority queue instantiation, you could instruct the priority queue to make use of a deque as well.
A priority queue organizes the data in such a way that the highest priority value appears first; in other words, the values are sorted in a descending order.
The deque and vector meet the requirements ...