Python Stack and Queue
Data structure organizes the storage in computers so that we can easily access and change data. Stacks and Queues are the earliest data structure defined in computer science. A simple Python list can act as a queue and stack as well. A queue follows FIFO rule (First In First Out) and used in programming for sorting. It is common for stacks and queues to be implemented with an array or linked list.
A Stack is a data structure that follows the LIFO(Last In First Out) principle. To implement a stack, we need two simple operations:
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A Queue follows the First-in-First-Out (FIFO) principle. It is opened from both the ends hence we can easily add elements to the back and can remove elements from the front.
To implement a queue, we need two simple operations:
Operations on Queue
Note: The implementation of a queue is a little bit different. A queue follows the "First-In-First-Out". Time plays an important factor here. The Stack is fast because we insert and pop the elements from the end of the list, whereas in the queue, the insertion and pops are made from the beginning of the list, so it becomes slow. The cause of this time difference is due to the properties of the list, which is fast in the end operation but slow at the beginning operations because all other elements have to be shifted one by one.
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