5. Inbuilt queue STL #

Created Thursday 23 January 2020

• Now we will focus only on the interface.

• Queue has been implemented in C++ STL. We will use only that now.

• header

• It’s a simple one sided queue

• declaration is small ‘q’, queue <> variable_name.

Interface:

1. push(data) - the same as our enqueue(). Inserts the element in the queue.
2. front() - returns the element at head if it exists, else generic value.
3. void pop() - deletes an element but does not return the deleted value. It is a void.
4. size() - same as our getSize(). Returns the size of the queue.
5. empty() - returns true if empty, else false.
6. back() - returns the element at the back.

Note: Both stack and queue have the exact same interfaces. With the same signatures. Only the working changes. pop and front are different!

• Print was not discussed here.

For both sides insertion and deletion, use .