What is the difference between a c++ queue and deque?

In C++, Queue and Deque are two distinct data structures with unique characteristics and purposes.

1. Line:

1. A queue is a data structure that follows the “First In, First Out” (FIFO) principle, much like waiting in line in real life.
2. You can only insert elements at the end of the queue and delete elements from the front.
3. There are only two operations: push (enqueue) and pop (dequeue).
4. In C++, a Queue is implemented using std::queue, with deque as the default container.

1. Double-ended queue:

1. A deque is a data structure with both queue and stack properties, allowing insertion and deletion operations at both ends.
2. You can insert and delete at both the front and end of the queue simultaneously.
3. Having more operations such as push_front (inserting at the front of the queue), push_back (inserting at the back of the queue), pop_front (deleting from the front of the queue), pop_back (deleting from the back of the queue), etc.
4. In C++, a Deque is implemented using std::deque.

Therefore, the main difference is that Deque is a data structure that has more operations and supports both queue and stack properties, while Queue only supports queue properties.