Queue

A Queue is a linear data structure that follows the First-In-First-Out (FIFO) principle. Elements are added at the rear and removed from the front. Common operations include enqueue and dequeue.

Queue Visualization

Queue is empty

Queue (FIFO): Empty

Complexity

Time Complexity: O(1) for enqueue/dequeue

Space Complexity: O(n)

Pseudocode

class Queue:
  function enqueue(item):
    queue.append(item)
  
  function dequeue():
    if queue is empty:
      return error
    return queue.remove_first()
  
  function front():
    return queue[0]

Related Algorithms

Stack

A Stack is a linear data structure that follows the Last-In-First-Out (LIFO) principle. Elements are added and removed from the same end (top). Common operations include push, pop, and peek.

Time: O(1) for push/pop/peek | Space: O(n)

Linked List

A Linked List is a linear data structure where elements are stored in nodes, and each node points to the next node. It allows dynamic memory allocation and efficient insertion/deletion operations.

Time: O(1) for insert/delete, O(n) for search | Space: O(n)