Python linked list problems

A linked list is a linear data structure where each element is a separate object.
Linked list elements are not stored at contiguous location; the elements are linked using pointers.

Each node of a list is made up of two items - the data and a reference to the next node. The last node has a reference to null. The entry point into a linked list is called the head of the list. It should be noted that head is not a separate node, but the reference to the first node. If the list is empty then the head is a null reference.

Linked List Representation
An example of a linked list node with an integer data.
  • C/C++
  • Java
  • Python
// Linked list example in C/C++ // A linked list node struct ListNode { int val; struct ListNode *next; };
// Linked list example in Java // Linked list class class ListNode { // head of list Node head; // Node class class Node { int val; Node next; // Constructor to create a new node Node(int v) { val = v; } } }
# Linked list example in Python # Node class class Node: # Function to initialize the node object def __init__(self, v): self.val = v # Assign value self.next = None # Initialize next as null # Linked List class class ListNode: # Function to initialize the Linked List def __init__(self): self.head = None

Important tutorials

1. Arrays Vs Linked Lists
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2. Linked List Implementation
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3. Doubly Linked List
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4. Doubly Linked List Implementation
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