Free A-Level Computer Science guide

A-Level Paper 2: algorithms and programming

A route through linked lists and object-oriented programming, with complete Python examples and questions to try.

Content owner: Michael Print · Written for A-Level learners · Checked against official specifications

Where should I start?

These guides focus on OCR A-Level Computer Science H446/02. The Paper 2 specification includes object-oriented techniques and algorithms for structures such as linked lists. The linked-list model also connects to OCR's data-structures content.

Begin with the data-structures section if nodes and references are new to you. Read the OOP guide first if Python classes, self or methods are the sticking point.

Choose a route

01 · Data structures

From nodes to linked lists

See what a node holds, how a reference joins nodes, and why traversal stops at None.

Open the full linked-list example

02 · Programming techniques

Object-oriented Python

Identify classes, objects, attributes and methods. Learn what __init__, self and double underscores do in a separate runnable example.

How the ideas connect

A linked list is a chain of nodes. Each node stores a value and a reference to the next node.
A Python class can define the shape and behaviour of one node.
Methods let the program read a value, set the next reference and traverse the chain.

Check your specification

OCR H446/02 is called Algorithms and programming. These pages teach the workshop's Python implementation, while exam questions can also use pseudocode or a different language. Check the exact depth required for your examination year.

These are independently written explanations and practice questions. CompSciTutoring.co.uk is not affiliated with or endorsed by an examination board. The marking guidance is indicative; always check the syllabus for your examination year.

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Need help applying this to unfamiliar questions?

Use the free examples first, then explore one-to-one tuition if guided practice would help.

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