Linked List Removal | Data Structures | Programming Tutorials

Introduction

In computer science, a linked list is a linear collection of data elements, in which linear order is not given by their physical placement in memory. Instead, each element points to the next. It is a data structure consisting of a collection of nodes which together represent a sequence. In this challenge, we will focus on removing duplicates from a linked list.

Skills Graph

%%%%{init: {'theme':'neutral'}}%%%% flowchart RL algorithm(("`Algorithm`")) -.-> algorithm/BasicAlgorithmsGroup(["`Basic Algorithms`"]) python(("`Python`")) -.-> python/BasicConceptsGroup(["`Basic Concepts`"]) python(("`Python`")) -.-> python/ControlFlowGroup(["`Control Flow`"]) python(("`Python`")) -.-> python/DataStructuresGroup(["`Data Structures`"]) python(("`Python`")) -.-> python/FunctionsGroup(["`Functions`"]) python(("`Python`")) -.-> python/ObjectOrientedProgrammingGroup(["`Object-Oriented Programming`"]) python(("`Python`")) -.-> python/AdvancedTopicsGroup(["`Advanced Topics`"]) python(("`Python`")) -.-> python/PythonStandardLibraryGroup(["`Python Standard Library`"]) algorithm/BasicAlgorithmsGroup -.-> algorithm/linked_lists("`Linked Lists`") python/BasicConceptsGroup -.-> python/variables_data_types("`Variables and Data Types`") python/ControlFlowGroup -.-> python/conditional_statements("`Conditional Statements`") python/ControlFlowGroup -.-> python/while_loops("`While Loops`") python/DataStructuresGroup -.-> python/lists("`Lists`") python/DataStructuresGroup -.-> python/tuples("`Tuples`") python/DataStructuresGroup -.-> python/sets("`Sets`") python/FunctionsGroup -.-> python/function_definition("`Function Definition`") python/FunctionsGroup -.-> python/default_arguments("`Default Arguments`") python/ObjectOrientedProgrammingGroup -.-> python/classes_objects("`Classes and Objects`") python/ObjectOrientedProgrammingGroup -.-> python/constructor("`Constructor`") python/ObjectOrientedProgrammingGroup -.-> python/polymorphism("`Polymorphism`") python/ObjectOrientedProgrammingGroup -.-> python/encapsulation("`Encapsulation`") python/AdvancedTopicsGroup -.-> python/iterators("`Iterators`") python/PythonStandardLibraryGroup -.-> python/data_collections("`Data Collections`") python/FunctionsGroup -.-> python/build_in_functions("`Build-in Functions`") subgraph Lab Skills algorithm/linked_lists -.-> lab-268847{{"`Removing Duplicates in Linked Lists`"}} python/variables_data_types -.-> lab-268847{{"`Removing Duplicates in Linked Lists`"}} python/conditional_statements -.-> lab-268847{{"`Removing Duplicates in Linked Lists`"}} python/while_loops -.-> lab-268847{{"`Removing Duplicates in Linked Lists`"}} python/lists -.-> lab-268847{{"`Removing Duplicates in Linked Lists`"}} python/tuples -.-> lab-268847{{"`Removing Duplicates in Linked Lists`"}} python/sets -.-> lab-268847{{"`Removing Duplicates in Linked Lists`"}} python/function_definition -.-> lab-268847{{"`Removing Duplicates in Linked Lists`"}} python/default_arguments -.-> lab-268847{{"`Removing Duplicates in Linked Lists`"}} python/classes_objects -.-> lab-268847{{"`Removing Duplicates in Linked Lists`"}} python/constructor -.-> lab-268847{{"`Removing Duplicates in Linked Lists`"}} python/polymorphism -.-> lab-268847{{"`Removing Duplicates in Linked Lists`"}} python/encapsulation -.-> lab-268847{{"`Removing Duplicates in Linked Lists`"}} python/iterators -.-> lab-268847{{"`Removing Duplicates in Linked Lists`"}} python/data_collections -.-> lab-268847{{"`Removing Duplicates in Linked Lists`"}} python/build_in_functions -.-> lab-268847{{"`Removing Duplicates in Linked Lists`"}} end

Remove Duplicates

Problem

Given a non-circular, singly linked list, remove duplicates from it. The goal is to modify the original list in place and return the head of the modified list.

Requirements

To solve this problem, we need to consider the following requirements:

The linked list is non-circular and singly linked.
None values cannot be inserted in the list.
We already have a linked list class that can be used for this problem.
Two solutions need to be implemented: one using additional data structures and one without.
The problem fits in memory.

Example Usage

Here are some examples of how the function should behave:

Empty linked list -> []
One element linked list -> [element]
General case with no duplicates -> [1, 2, 3, 4]
General case with duplicates -> [1, 2, 3]

Summary

In this Python challenge, we learned how to remove duplicates from a linked list. We explored the requirements and constraints of the problem and provided examples of how the program should behave. By solving this challenge, you can improve your understanding of linked lists and the associated algorithms.

Removing Duplicates in Linked Lists