Pseudo-code is a way of writing an algorithm using programming keywords and ordinary words. Pseudo-code cannot be compiled, but any programmer can read it.

How is input written in pseudo-code?

An input is written as INPUT name, which reads a value into that variable. The variable then holds the value for later steps.

How is output written in pseudo-code?

An output is written as OUTPUT total, which displays the value held. Text in quotation marks can be output in the same way.

Why are keywords written in capitals in pseudo-code?

Capitals separate the keywords of the algorithm from the identifiers chosen by the programmer. The structure is then obvious at a glance.

Why is pseudo-code indented?

Indentation shows which statements belong inside a selection or a loop. The nesting of the constructs becomes visible.

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Boolean Logic and Simplification

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Algorithms, Pseudo-Code and Programming Constructs

Topic overview Algorithms and how they are defined Pseudo-code conventions Flowcharts and flowchart symbols Sequence and selection Repetition: count-controlled and condition-controlled loops Counts, totals and rogue values Tracing, altering and writing algorithms

Variables, Scope, Parameters and Identifiers

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System Design and Human-Computer Interaction

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Software Engineering Tools and Translators

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Computing, Society and the Law

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Computer Architecture, the Processor and Assembly Language

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Input, Output and Secondary Storage

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Data Transmission and Network Performance

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Number Systems and Binary Arithmetic

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Data Types, Characters and Floating Point

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Files, Records and File Organisation

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Databases, Normalisation and Entity Modelling

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SQL, Big Data and Distributed Systems

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The Operating System and Its Modes

Topic overview The need for an operating system and the role of the kernel Managing peripherals, processes and memory protection The user interface and the layers between user and hardware Directory structures and file attributes Utility software Batch processing, real time control and real time transaction systems Types of operating system: single-user, multi-user, multi-tasking and multi-programming Designing an interface for different users and environments

Interrupts, Memory Management and Scheduling

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Types of Software System

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Data Security, Cryptography and Attack

Topic overview Online updating and the integrity of shared files Dangers of holding personal data Clerical procedures, access levels, passwords and write protection Cryptography: its purpose, and symmetric and asymmetric keys Hashing, digital signatures and certificates Caesar and Vernam ciphers and comparing cipher strength Biometric technologies and their limitations Threats, damage and contingency planning Malicious software, hacking and penetration testing

Algorithms, Pseudo-Code and Programming Constructs

Pseudo-code conventions

3 things to know
Component 1

Overview

The house notation for assignment, input, output, selection and repetition — what a written answer is expected to look like when no real language is named.

What you need to know

Answer each one before you reveal it.

Your recallNot started

Key term

How are assignment and input written in pseudo-code?

Key term

What is pseudo-code?

Key term

How is a value assigned to a variable in pseudo-code?

Questions from this subtopic

Each one with the model answer underneath.

1
What is pseudo-code?
Model answer
Pseudo-code is a way of writing an algorithm using programming keywords and ordinary words. Pseudo-code cannot be compiled, but any programmer can read it.
2
How is a value assigned to a variable in pseudo-code?
Model answer
An assignment is written as total = 0, with the variable on the left. The value on the right is copied into the variable.
3
How is input written in pseudo-code?
Model answer
An input is written as INPUT name, which reads a value into that variable. The variable then holds the value for later steps.
4
How is output written in pseudo-code?
Model answer
An output is written as OUTPUT total, which displays the value held. Text in quotation marks can be output in the same way.
5
Why are keywords written in capitals in pseudo-code?
Model answer
Capitals separate the keywords of the algorithm from the identifiers chosen by the programmer. The structure is then obvious at a glance.
6
Why is pseudo-code indented?
Model answer
Indentation shows which statements belong inside a selection or a loop. The nesting of the constructs becomes visible.

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Data Structures: Arrays, Records and Hash Tables

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