queue

Learn to use Queue in Java Collections Framework

In this article, we will take a look at how to use the Queue class in Java Collections library. This is useful as one can directly use queue without natively implementing it

data structure

Priority Queue

Priority queue is an abstract data type which is like a queue or stack data structure with each element having a priority assigned to it. In priority queue, an element with highest priority assigned is served first, if two elements have same priority then they are served according to enqueue order

data structure

Implementing Stack using queues in two ways

A stack is based on the principle of Last-in-First-Out(LIFO). It is commonly used abstract data type with two major operations, namely pop and push. Push() and pop() are carried out in the topmost element, which is the item most recently added to the stack. Push operation adds an element to stack

C++

Queue in C++ STL

Queue in the STL of C++ is a dynamically resizing container to implement the queue data structure. It is a sequential linear container which follows the First In First Out(FIFO) arrangement. We explore the various functions like empty, size, swap, emplace, front, back, push and pop operations

data structure

Circular Queue / Ring Buffer / Circular Buffer

Circular Queue (Ring Buffer) is also a linear data structure, which follows the principle of FIFO(First In First Out), but instead of ending the queue at the last position, it again starts from the first position after the last, hence making the queue behave like a circular data structure.

data structure

Implementing Queue using Stack in two ways

Queue is an abstract data structure similar to Stacks. Queue is open at both its ends. One end is always used to insert data (enqueue) and the other is used to remove data (dequeue). For implementing queue using stack, one method is to make dequeue costly and other is to make enqueue costly

algorithm

Cartesian tree sorting

Cartesian tree sorting, also called Levcopoulos Petersson algorithm is an adaptive sorting algorithm, i.e. it performs much better on a partially sorted data. It needs two data structures a Cartesian tree and a priority queue. The algorithm here uses min-heap Cartesian tree to give a sorted sequence

data structure

Implementing Queue using Linked list

A queue (First in First out) is an ordered collection of items where the addition of new items happens at one end, called the rear, and removal of existing items occurs at the other end called front. It can be implemented using Linked Lists which brings many advantages over array implementation

data structure

Queue is a linear data structure that can be used to store data in order by imposing rules on data insertion and deletion. It has found immense use and can be implemented using arrays and linked lists. The operations include enqueue and dequeue which are of O(1) time complexity with space of O(N)

double ended queue

Double Ended Queue (Deque)

A double ended queue also called as deque (pronounced as ‘deck’ or ‘dequeue’) is a list in which the elements can be inserted or deleted at either end in constant time.