Beginning Programming All-in-One For Dummies E-Book

Wallace Wang

• Herausgeber: John Wiley & Sons
• Kategorie: Wissenschaft und neue Technologien
• Sprache: Englisch

Seitenzahl: 990

Veröffentlichungsjahr: 2022

Beschreibung

Let there be code! Beginning Programming All-in-One For Dummies offers one guide packed with 7 books to teach you programming across multiple languages. Coding can seem complex and convoluted, but Dummies makes it simple and easy to understand. You'll learn all about the principles of programming, algorithms, data structures, debugging programs, unique applications of programming and more while learning about some of the most popular programming languages used today. Move confidently forward in your computer science coursework or straight into the workforce. You'll come away with a rock-solid foundation in the programming basics, using data, coding for the web, and building killer apps. * Learn the basics of coding, including writing and compiling code, using algorithms, and data structures * Get comfortable with the syntax of several different programming languages * Wrap your mind around interesting programming opportunities such as conducting biological experiments within a computer or programming a video game engine * Develop cross-platform applications for desktop and mobile devices This essential guide takes the complexity and convolution out of programming for beginners and arms you with the knowledge you need to follow where the code takes you.

Leseprobe

Beginning Programming All-in-One For Dummies®, 2nd Edition

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Library of Congress Control Number: 2022936302

ISBN 978-1-119-88440-8 (pbk); ISBN 978-1-119-88441-5 (ebk); ISBN 978-1-119-88442-2 (ebk)

Beginning Programming All-in-One For Dummies®

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Table of Contents

Cover

Title Page

Copyright

Introduction

About This Book

Foolish Assumptions

Icons Used in This Book

Beyond the Book

Where to Go from Here

Book 1: Getting Started with Programming

Chapter 1: Getting Started Programming a Computer

How Computer Programming Works

The History of Computer Programming

Figuring Out Programming

Chapter 2: Different Methods for Writing Programs

Spaghetti Programming

Structured Programming

Event-Driven Programming

Object-Oriented Programming

Using Protocol-Oriented Programming

Design Patterns

Chapter 3: Types of Programming Languages

Your First Language

Curly-Bracket Languages

Artificial Intelligence Languages

Scripting Languages

Database Programming Languages

Comparing Programming Languages

Chapter 4: Programming Tools

Choosing a Compiler

Finding an Interpreter

Compiling to a Virtual Machine

Writing a Program with an Editor

Fixing a Program with a Debugger

Saving Time with Third-Party Components

Optimizing a Program with a Profiler

Managing Source Code

Creating a Help File

Installing a Program

Dissecting Programs with a Disassembler

Book 2: Programming Basics

Chapter 1: How Programs Work

Using Keywords as Building Blocks

Organizing a Program

Dividing a Program into Subprograms

Dividing a Program into Objects

Creating a User Interface

Chapter 2: Variables, Data Types, and Constants

Declaring Variables

Using Different Data Types

Storing Data in a Variable

Retrieving Data from a Variable

Using Constant Values

Defining the Scope of a Variable

Chapter 3: Manipulating Data

Storing Data with the Assignment Operator

Using Math to Manipulate Numbers

Manipulating Strings

Finding Strings with Regular Expressions

Using Comparison Operators

Using Boolean Operators

Converting Data Types

Chapter 4: Making Decisions by Branching

Picking One Choice with the IF-THEN Statement

Picking Two Choices with the IF-THEN-ELSE Statement

Picking Three or More Choices with the IF-THEN-ELSEIF Statement

Playing with Multiple Boolean Operators

Making Multiple Choices with the SELECT CASE Statement

Chapter 5: Repeating Commands by Looping

Looping a Fixed Number of Times with the FOR-NEXT Loop

Looping Zero or More Times with the WHILE Loop

Looping at Least Once with the DO Loop

Playing with Nested Loops

Prematurely Exiting from a Loop

Checking Your Loops

Chapter 6: Breaking a Large Program into Subprograms

Creating and Using Subprograms

Passing Parameters

Repeating a Subprogram with Recursion

Chapter 7: Breaking a Large Program into Objects

How Object-Oriented Programming Works

Encapsulation Isolates Data and Subprograms

Sharing Code with Inheritance

Polymorphism: Modifying Code without Changing Its Name

Design Patterns

Object-Oriented Languages

Real-Life Programming Examples

Chapter 8: Reading and Saving Files

Storing Data in Text Files

Storing Fixed-Size Data in Random-Access Files

Storing Varying-Size Data in Untyped Files

Using Database Files

Chapter 9: Documenting Your Program

Adding Comments to Source Code

Writing Software Documentation

Chapter 10: Principles of User Interface Design

The Evolution of User Interfaces

Elements of a User Interface

Designing a User Interface

Chapter 11: Debugging and Testing

Common Types of Programming Errors

Debugging with Comments and Print Statements

Breakpoints, Stepping, and Watching

Testing Code

Book 3: Data Structures

Chapter 1: Structures and Arrays

Using Structures

Using an Array

Working with Resizable Arrays

Working with Multidimensional Arrays

Using Structures with Arrays

Drawbacks of Arrays

Chapter 2: Sets and Linked Lists

Using Sets

Using Linked Lists

Drawbacks of Sets and Linked Lists

Chapter 3: Collections and Dictionaries

Using a Collection

Using Dictionaries

Understanding Hash Tables

Chapter 4: Stacks, Queues, and Deques

Using Stacks

Using Queues

Using Deques

Chapter 5: Graphs and Trees

Understanding Graphs

Creating Trees

Taking Action on Trees

Book 4: Algorithms

Chapter 1: Sorting Algorithms

Using Bubble Sort

Using Selection Sort

Using Insertion Sort

Using Shell Sort

Using Heap Sort

Using Merge Sort

Using Quick Sort

Comparing Sorting Algorithms

Chapter 2: Searching Algorithms

Sequential Search

Using Indexes

Adversarial Search

Chapter 3: String Searching

Sequential Text Search

Searching with Regular Expressions

Searching Phonetically

Chapter 4: Data Compression Algorithms

Lossless Data Compression Algorithms

Lossy Data Compression

Chapter 5: Encryption Algorithms

How Encryption Works

The Basics of Encryption

Symmetric/Asymmetric Encryption Algorithms

Cracking Encryption

Book 5: Web Programming

Chapter 1: HyperText Markup Language

The Structure of an HTML Document

Adding Graphics

Defining the Background

Creating Hyperlinks

Making Tables

Chapter 2: CSS

The Structure of a Stylesheet

Creating Style Classes

Separating Styles in Files

Cascading Stylesheets

Chapter 3: JavaScript

The Structure of a JavaScript Program

Creating Comments

Declaring Variables

Using Operators

Branching Statements

Looping Statements

Creating Functions

Using Arrays

Designing User Interfaces

Chapter 4: PHP

Examining the Structure of a PHP Program

Creating Comments

Declaring Variables

Using Operators

Branching Statements

Looping Statements

Creating Functions

Using Arrays

Creating Objects

Chapter 5: Ruby

The Structure of a Ruby Program

Creating Comments

Declaring Variables

Using Operators

Branching Statements

Looping Statements

Creating Functions

Using Data Structures

Creating Objects

Book 6: Programming Language Syntax

Chapter 1: C and C++

Looking at the Structure of a C/C++ Program

Creating Comments

Declaring Variables

Using Operators

Branching Statements

Looping Statements

Creating Functions

Data Structures

Using Objects

Chapter 2: Java and C#

Looking at the Structure of a Java/C# Program

Creating Comments

Declaring Variables

Using Operators

Branching Statements

Looping Statements

Creating Functions

Data Structures

Using Objects

Chapter 3: Perl and Python

Reviewing the Structure of a Perl or Python Program

Creating Comments

Defining Variables

Using Operators

Branching Statements

Looping Statements

Creating Functions

Making Data Structures

Using Objects

Chapter 4: Kotlin

Looking at the Structure of a Kotlin Program

Creating Comments

Declaring Variables

Declaring Constants

Using Operators

Branching Statements

Looping Statements

Creating Functions

Creating Data Structures

Creating Objects

Chapter 5: Swift and SwiftUI

Considering the Structure of a Swift Program

Creating Comments

Declaring Variables

Declaring Constants

Using Operators

Branching Statements

Looping Statements

Creating Functions

Data Structures

Creating Objects

Chapter 6: Flutter and Dart

Working with Flutter

Understanding the Dart Language

Book 7: Applications

Chapter 1: Database Management

Understanding the Basics of Databases

Manipulating Data

Database Programming

Chapter 2: Bioinformatics

The Basics of Bioinformatics

Database Searches

Bioinformatics Programming

Chapter 3: Computer Security

Stopping Malware

Stopping Hackers

Secure Computing

Chapter 4: Artificial Intelligence

Problem Solving

Machine Learning

Applications of Artificial Intelligence

Chapter 5: Mobile and Wearable Computing

Understanding the Different Generations of Computing

Giving Data to the User

Getting Data from the User

Tracking Motion and Location

Tracking Real-Time Health Data

Looking to the Future of Augmented Reality and Wearable Computers

Chapter 6: Game Engines

Understanding Game Engines

Picking a Game Engine

Programming a Game Engine

Exploring the Future Uses of Game Engines

Chapter 7: The Future of Computer Programming

Picking a Programming Language

Picking an Operating System

Doing Cross-Platform Programming

Defining Your Future in Programming

Index

About the Author

Advertisement Page

Connect with Dummies

End User License Agreement

List of Tables

Book 1 Chapter 3

TABLE 3-1 Popular “Battling Robot” Programming Games

Book 2 Chapter 2

TABLE 2-1 Typical Storage Requirements for Different Data Types

Book 2 Chapter 3

TABLE 3-1 Examples of Using the Assignment (=) Operator

TABLE 3-2 Common Mathematical Operators

TABLE 3-3 Operator Precedence

TABLE 3-4 Common Built-In Math Functions

TABLE 3-5 Common Built-In String Functions

TABLE 3-6 Examples of Pattern-Matching with Different Regular Expressions

TABLE 3-7 Common Comparison Operators

TABLE 3-8 The And Truth Table

TABLE 3-9 The Or Truth Table

TABLE 3-10 The Xor Truth Table

Book 2 Chapter 4

TABLE 4-1 Multiple Boolean Expressions Ultimately Evaluate to a Single True or F...

Book 2 Chapter 5

TABLE 5-1 A Database of Employee Names Assigned with Specific Employee ID Number...

Book 4 Chapter 1

TABLE 1-1 Comparison of Different Sorting Algorithms

Book 4 Chapter 3

TABLE 3-1 Single Pattern Regular Expressions

TABLE 3-2 Calculating a Soundex Code

Book 4 Chapter 4

TABLE 4-1 Rotating and Sorting Data

Book 5 Chapter 1

TABLE 1-1 HTML Color Codes

Book 5 Chapter 3

TABLE 3-1 Mathematical Operators

TABLE 3-2 Relational Operators

TABLE 3-3 Logical Operators

TABLE 3-4 Assignment Operators

Book 5 Chapter 4

TABLE 4-1 Mathematical Operators

TABLE 4-2 Relational Operators

TABLE 4-3 Logical operators

TABLE 4-4 Assignment Operators

Book 5 Chapter 5

TABLE 5-1 Mathematical Operators

TABLE 5-2 Relational Operators

TABLE 5-3 Logical Operators

TABLE 5-4 Assignment Operators

Book 6 Chapter 1

TABLE 1-1

Typical Storage and Range Limitations of C/C++ Integer Data Types

TABLE 1-2

Typical Floating-Point Data Types

TABLE 1-3

Mathematical Operators

TABLE 1-4

Relational Operators

TABLE 1-5

Logical Operators

TABLE 1-6

Assignment Operators

Book 6 Chapter 2

TABLE 2-1 Typical Storage and Range Limitations of Java Integer Data Types

TABLE 2-2 Typical Storage and Range Limitations of C# Integer Data Types

TABLE 2-3 Typical Floating Point-Data Types

TABLE 2-4 Mathematical Operators

TABLE 2-5 Relational Operators

TABLE 2-6 Logical Operators

TABLE 2-7 Assignment Operators

Book 6 Chapter 3

TABLE 3-1 Mathematical Operators

TABLE 3-2 Relational Operators

TABLE 3-3 Using Perl's Comparison with Signed Result Operator

TABLE 3-4 Logical Operators

TABLE 3-5 Assignment Operators

Book 6 Chapter 4

TABLE 4-1 Kotlin Integer Data Types

TABLE 4-2 Kotlin Floating-Point Data Types

TABLE 4-3 Mathematical Operators

TABLE 4-4 Relational Operators

TABLE 4-5 Logical Operators

Book 6 Chapter 5

TABLE 5-1 Swift Integer Data Types

TABLE 5-2 Swift Decimal Data Types

TABLE 5-3 Mathematical Operators

TABLE 5-4 Relational Operators

TABLE 5-5 Logical Operators

Book 6 Chapter 6

TABLE 6-1 Mathematical Operators

TABLE 6-2 Relational Operators

TABLE 6-3 Logical Operators

TABLE 6-4 Assignment Operators

Book 7 Chapter 5

TABLE 5-1 Understanding the Different Generations of Computing

List of Illustrations

Book 1 Chapter 1

FIGURE 1-1: A processor uses its registers to temporarily store data.

FIGURE 1-2: An editor lets you write and edit the source code of a program.

Book 1 Chapter 2

FIGURE 2-1: Constantly modifying a program eventually creates an unorganized me...

FIGURE 2-2: Sequences consist of groups of commands that the computer follows, ...

FIGURE 2-3: Branches let the computer choose which group of commands to run at ...

FIGURE 2-4: You can store subprograms in one big file or in separate files.

FIGURE 2-5: Designing a UI involves drawing what you want to appear on your pro...

FIGURE 2-6: Properties define how each part of a UI looks and behaves.

FIGURE 2-7: An event handler tells the UI how to behave when the user does some...

FIGURE 2-8: Object-oriented programming never physically copies code but “point...

Book 1 Chapter 3

FIGURE 3-1: Programming in Scratch means connecting visual building blocks toge...

FIGURE 3-2: LEGO Mindstorms programming connects visual building blocks togethe...

FIGURE 3-3: An Alice program creates an animated character onscreen and moves i...

FIGURE 3-4: Using a battling robot to study programming can make programming mo...

FIGURE 3-5: The .NET framework can tie programs, written in multiple languages,...

FIGURE 3-6: Recording keystrokes automatically creates the equivalent VBA code ...

Book 1 Chapter 4

FIGURE 4-1: Compiler optimization settings let you make your program as small a...

FIGURE 4-2: A cross-compiler lets you write a program and compile it for multip...

FIGURE 4-3: The Flutter website lets you type and run code using any browser.

FIGURE 4-4: A virtual machine acts like a combination of an interpreter and a c...

FIGURE 4-5: An IDE provides access to multiple programming tools within a singl...

FIGURE 4-6: Stepping through a program, line-by-line, can help you find errors ...

FIGURE 4-7: Breakpoints let you skip over parts of your program that you don’t ...

FIGURE 4-8: The

step over

command lets you skip, or “step over,” the lines stor...

FIGURE 4-9: Watching and changing variables can show you how a program reacts t...

Book 2 Chapter 1

FIGURE 1-1: If you put enough commands together, you can create any type of pro...

FIGURE 1-2: Multiple keywords, along with various symbol characters, can create...

FIGURE 1-3: Dividing a large program into parts can make it easier to find spec...

FIGURE 1-4: Subprograms create reusable building blocks that you can use to mak...

FIGURE 1-5: Storing subprograms in separate files can make it easier to read an...

FIGURE 1-6: Subprograms give you the option of using different programming lang...

FIGURE 1-7: Changing one part of a program can affect other parts of that same ...

FIGURE 1-8: Object-oriented programming divides your program into logical parts...

FIGURE 1-9: The UI accepts data and displays the results of its calculations ba...

FIGURE 1-10: Creating a UI involves picking common items, such as buttons and c...

Book 2 Chapter 2

FIGURE 2-1: If a program tries to store the wrong type of data in a variable, t...

FIGURE 2-2: You can’t compile your program until the compiler is certain that y...

FIGURE 2-3: Different data types that can hold a range of values.

FIGURE 2-4: Assigning a new value to a variable wipes out the old value.

FIGURE 2-5: Every part of a program can access and change a global variable.

FIGURE 2-6: Module variables restrict access to code stored in a particular fil...

FIGURE 2-7: Subprogram variables restrict access only to code stored in that pa...

FIGURE 2-8: To share data among subprograms, you have to pass that data from on...

Book 2 Chapter 4

FIGURE 4-1: A simple

IF-THEN

statement runs one extra command if something is

T

...

FIGURE 4-2: An

IF-THEN-ELSE

statement offers two different sets of commands to ...

FIGURE 4-3: An

IF-THEN-ELSEIF

statement offers two different sets of commands t...

Book 2 Chapter 5

FIGURE 5-1: A loop can run one or more commands over and over.

FIGURE 5-2: The

WHILE

loop keeps running as long as a certain condition remains...

FIGURE 5-3: A nested loop appears inside another loop.

Book 2 Chapter 6

FIGURE 6-1: Every large program is made up of smaller subprograms that act as b...

FIGURE 6-2: Reusing subprograms can make writing new programs easier and faster...

FIGURE 6-3: Subprograms let you remove and isolate commands out of your main pr...

FIGURE 6-4: Subprograms usually appear at the beginning or end of a file.

FIGURE 6-5: When you call a subprogram, you may also need to pass parameters to...

FIGURE 6-6: Normally when you pass parameters to a subprogram, the computer mak...

FIGURE 6-7: Passing by reference means the subprogram can manipulate data that ...

FIGURE 6-8: Recursion makes multiple copies of the same subprogram.

Book 2 Chapter 7

FIGURE 7-1: Dividing a program into tasks can obscure the actual purpose of a p...

FIGURE 7-2: Object-oriented programming divides a large program into objects th...

FIGURE 7-3: The parts of a typical object.

FIGURE 7-4: Changing a subprogram can wreck a perfectly working program.

FIGURE 7-5: Encapsulation isolates a chunk of code as an independent object.

FIGURE 7-6: If you modify a subprogram, you need to create a separate copy of t...

FIGURE 7-7: Inheritance lets you reuse another object’s subprograms without phy...

FIGURE 7-8: Objects contain code that’s unique to only that object.

FIGURE 7-9: Polymorphism lets you reuse a method name in another object.

FIGURE 7-10: An interface pattern provides an object-oriented interface to a no...

FIGURE 7-11: The flyweight pattern simplifies objects that contain repetitive i...

FIGURE 7-12: The memento pattern uses one object to store information about ano...

Book 2 Chapter 8

FIGURE 8-1: A record organizes related data together.

FIGURE 8-2: The fixed size of each record makes it easy to identify the physica...

FIGURE 8-3: Untyped files contain records that can vary in size.

FIGURE 8-4: The computer can retrieve data from an untyped file in blocks or ch...

FIGURE 8-5: By defining which chunk of data you want to retrieve, you can retri...

FIGURE 8-6: Database files are divided into tables, and each table is further d...

FIGURE 8-7: Relational databases link tables to group logically related informa...

FIGURE 8-8: Database toolkits take care of the technical details of manipulatin...

FIGURE 8-9: A database toolkit can manipulate data using a familiar database la...

FIGURE 8-10: Programs often act as a front end to a database file.

Book 2 Chapter 10

FIGURE 10-1: The user interface lets you control a program, give it commands, a...

FIGURE 10-2: Early user interfaces were simple menus of keystroke combinations.

FIGURE 10-3: Drop-down lists help organize commands and tuck them out of sight ...

FIGURE 10-4: Buttons can display the entire command name for the user to see.

FIGURE 10-5: Submenus reduce the number of commands in a drop-down list but mak...

FIGURE 10-6: Icons, organized in toolbars, allow one-click access to multiple c...

FIGURE 10-7: Toolboxes provide another way to group icons for easy access.

FIGURE 10-8: Users can type any information inside a text box, including invali...

FIGURE 10-9: Radio buttons can display multiple choices, but they only let you ...

FIGURE 10-10: Check boxes can display multiple choices and allow users to pick ...

FIGURE 10-11: List boxes display a list of options.

FIGURE 10-12: Combo boxes let you either make a choice or type data directly.

FIGURE 10-13: A slider lets users visually choose a numeric value or setting by...

FIGURE 10-14: A user interface displays data in a window that users can manipul...

FIGURE 10-15: Dialog boxes ask the user for more data before carrying out a com...

FIGURE 10-16: Boxes draw lines to separate and organize different user interfac...

FIGURE 10-17: Tabs let you organize and display different user interface items ...

FIGURE 10-18: This program’s drop-down list lets you view a bunch of submenus t...

FIGURE 10-19: A cryptic error message is meaningless and frustrating because th...

FIGURE 10-20: Customization options let a user change the user interface to sui...

Book 2 Chapter 11

FIGURE 11-1: Code snippets can provide templates for writing common statements.

FIGURE 11-2: Code completion displays several commands so you can choose the on...

FIGURE 11-3: Breakpoints identify lines of code where you want the program to s...

FIGURE 11-4: Conditional breakpoints can halt execution only if specific condit...

FIGURE 11-5: You can often select different debugging information to use in a p...

Book 3 Chapter 1

FIGURE 1-1: A structure can contain multiple fields.

FIGURE 1-2: An array can hold multiple chunks of data.

FIGURE 1-3: One-based arrays number array elements differently than zero-based ...

FIGURE 1-4: Some programming languages let you define the numbering of an array...

FIGURE 1-5: By defining your own numbering for an array, you can make those num...

FIGURE 1-6: Resizing an array lets you expand or shrink an array.

FIGURE 1-7: A two-dimensional array lets you store data in a grid.

FIGURE 1-8: A structure can hold only one group of related data, but an array o...

FIGURE 1-9: An array of structures acts like a simple database.

FIGURE 1-10: Inserting data into an array means copying and moving data from on...

Book 3 Chapter 2

FIGURE 2-1: Adding and removing data in a set is easier than adding and removin...

FIGURE 2-2: The

union

command combines data from two sets to create a third set...

FIGURE 2-3: The

intersection

command takes only data common in both sets and st...

FIGURE 2-4: The

difference

command strips out data in common with a second set.

FIGURE 2-5: The order in which you list set names with the

difference

command d...

FIGURE 2-6: A node consists of a pointer and one or more variables to store dat...

FIGURE 2-7: A linked list stores data in each node that points to another node.

FIGURE 2-8: Rearranging the order of a linked list is as simple as rearranging ...

FIGURE 2-9: Adding data from a linked list also involves rearranging pointers.

FIGURE 2-10: Deleting data from a linked list involves removing data and then r...

FIGURE 2-11: A double linked list lets you traverse a linked list in both direc...

FIGURE 2-12: A circular linked list has no beginning or end.

FIGURE 2-13: Pointers must always point to a valid node of a linked list.

Book 3 Chapter 3

FIGURE 3-1: Collections expand automatically each time you store new data.

FIGURE 3-2: You can insert data before a specific location in an array.

FIGURE 3-3: You can insert new data after an existing location in a collection.

FIGURE 3-4: When you remove data from a collection, the collection renumbers th...

FIGURE 3-5: Identify data by its location or by a key.

FIGURE 3-6: Retrieving data by index numbers is unreliable because they can cha...

FIGURE 3-7: Hash tables make searching faster by dividing data into distinct se...

FIGURE 3-8: Hash tables convert each key into a numeric value.

FIGURE 3-9: Chaining lets a single hash value point to a list of multiple items...

FIGURE 3-10: Double hashing creates miniature hash tables within a larger hash ...

Book 3 Chapter 4

FIGURE 4-1: Stacks store the oldest data on the bottom and the newest data on t...

FIGURE 4-2: When you add data to a stack, the oldest data keeps getting pushed ...

FIGURE 4-3: The Peek command retrieves data, but the

Pop

command retrieves and ...

FIGURE 4-4: The

Undo

command offered in most programs can be easily implemented...

FIGURE 4-5: The queue data structure mimics a line of people.

FIGURE 4-6: The oldest data appears at the front while the newest data appears ...

FIGURE 4-7: The

Peek

command retrieves data, but the

Dequeue

command retrieves ...

FIGURE 4-8: A deque acts like a two-way queue.

FIGURE 4-9: Each node in a deque contains two pointers that point to the next a...

FIGURE 4-10: Two ways to implement a deque as a linked list.

FIGURE 4-11: A deque can grow in two different directions.

FIGURE 4-12: A deque could be used by an antivirus program to scan messages.

Book 3 Chapter 5

FIGURE 5-1: Modeling a map of different cities.

FIGURE 5-2: A graph data structure can model the mapping problem better than an...

FIGURE 5-3: The three types of graphs.

FIGURE 5-4: The Seven Bridges of Königsberg represented as a graph.

FIGURE 5-5: A tree is a hierarchical graph.

FIGURE 5-6: A tree consists of one root node and multiple leaf and internal nod...

FIGURE 5-7: A tree can organize names alphabetically by last name.

FIGURE 5-8: An ordered binary tree stores and sorts data by value.

FIGURE 5-9: An ordinary tree is more difficult to search than an ordered binary...

FIGURE 5-10: In a B-tree, all leaf nodes appear at the same level.

FIGURE 5-11: The four different ways to traverse a tree.

FIGURE 5-12: Inserting new data in an ordered binary tree.

FIGURE 5-13: After deleting data from a tree, you may need to rearrange the rem...

FIGURE 5-14: Pruning a tree removes two or more nodes from a tree.

FIGURE 5-15: Grafting a sub-tree can require rearranging the entire modified tr...

FIGURE 5-16: A tree can help a computer plan its next move.

Book 4 Chapter 1

FIGURE 1-1: A bubble sort repetitively compares two adjacent items.

FIGURE 1-2: The bubble sort algorithm examines the entire list of data several ...

FIGURE 1-3: Selection sort repetitively moves the smallest value to the front o...

FIGURE 1-4: Insertion sort only examines a list once to sort it.

FIGURE 1-5: Shell sort performs multiple insertion sorts on parts of a long lis...

FIGURE 1-6: Valid and invalid heap binary trees.

FIGURE 1-7: Heap sort uses a tree data structure to sort and store items tempor...

FIGURE 1-8: An array can mimic a heap data structure.

FIGURE 1-9: Manipulating data in an array that mimics a heap.

FIGURE 1-10: Merge sort breaks a long list into several smaller lists and then ...

FIGURE 1-11: Quick sort repetitively divides a large list into two smaller list...

Book 4 Chapter 2

FIGURE 2-1: The speed of sequential search depends directly on the size of the ...

FIGURE 2-2: Sequential search can be made faster by searching from either the f...

FIGURE 2-3: Block searching can speed up a sequential search on sorted data.

FIGURE 2-4: Binary searching divides a list in half until it eventually finds i...

FIGURE 2-5: Interpolation searching tries to jump straight to the approximate l...

FIGURE 2-6: Fibonacci numbers divide and search a list more efficiently than a ...

FIGURE 2-7: Comparison of hash tables and indexes.

FIGURE 2-8: Clustered indexes physically rearrange data, whereas unclustered in...

FIGURE 2-9: A tree can analyze the best possible move.

FIGURE 2-10: Assigning values to possible moves helps the computer evaluate the...

Book 4 Chapter 3

FIGURE 3-1: Sequential search examines every character.

FIGURE 3-2: The Boyer–Moore algorithm skips over partially matched characters.

FIGURE 3-3: The Rabin–Karp algorithm searches for hash values.

FIGURE 3-4: The Shift Or algorithm creates an array of matching characters.

FIGURE 3-5: The Shift Or algorithm creates a two-dimensional array.

FIGURE 3-6: A finite state machine consists of nodes and arrows.

Book 4 Chapter 4

FIGURE 4-1: Reconstructing the original data from the BWT transformation.

FIGURE 4-2: Uncompressing data requires using a dictionary to replace codes wit...

FIGURE 4-3: The LZ77 algorithm replaces redundant data with pointers.

FIGURE 4-4: The LZW algorithm stores increasingly larger strings as numbers.

FIGURE 4-5: Comparison of compressed graphic images.

Book 4 Chapter 5

FIGURE 5-1: How a stream cipher works.

FIGURE 5-2: The electronic codebook encrypts blocks of data separately with the...

FIGURE 5-3: Cipher-block chaining uses the output from one block as the input f...

FIGURE 5-4: A single password can encrypt and decrypt a message.

FIGURE 5-5: Public keys encrypt data, and private keys decrypt data.

FIGURE 5-6: Public-key and private-key encryption can work together.

Book 5 Chapter 1

FIGURE 1-1: HTML can create six different headings.

FIGURE 1-2: You can specify text to appear center- or right-aligned.

FIGURE 1-3: The

<th>

and

</th>

tags define the headings for the...

FIGURE 1-4: The

<tr>

and

<td>

tags define new rows and data for...

FIGURE 1-5: The

<caption>

and

</caption>

tags define text to ap...

FIGURE 1-6: The

colspan

attribute lets text expand across multiple columns.

Book 6 Chapter 5

FIGURE 5-1: A storyboard lets you visually design a user interface.

FIGURE 5-2: The parts of a SwiftUI program.

FIGURE 5-3: Modifiers affect a View displayed in the Canvas pane.

FIGURE 5-4: State variables let changed data appear in multiple locations autom...

FIGURE 5-5: Swift allows Unicode characters to be used in variable names.

Book 6 Chapter 6

FIGURE 6-1: Adding properties can change the appearance of the

Text

widget.

FIGURE 6-2: The

Expanded

widget inside the

Row

widget can space items apart.

FIGURE 6-3: The

Column

widget arranges widgets vertically.

Book 7 Chapter 1

FIGURE 1-1: A free-form database can store randomly structured information.

FIGURE 1-2: A flat-file database stores data in fields and records.

FIGURE 1-3: A relational database is divided into tables.

FIGURE 1-4: Flat-file databases must store duplicate data in separate files.

FIGURE 1-5: Tables separate data into pieces.

FIGURE 1-6: Relational databases let you combine data from different tables.

FIGURE 1-7: The Select command retrieves a single record or tuple.

FIGURE 1-8: The Project command retrieves selected columns or attributes.

FIGURE 1-9: The Join command matches two or more tables together.

FIGURE 1-10: The three parts of a database program.

Book 7 Chapter 2

FIGURE 2-1: A bioinformatics program can help you search through large amounts ...

Book 7 Chapter 3

FIGURE 3-1: Firewalls can block ports or certain programs from accessing a netw...

Book 7 Chapter 4

FIGURE 4-1: A neural network.

FIGURE 4-2: How a neuron processes and outputs a value.

Book 7 Chapter 5

FIGURE 5-1: Constraints define the placement of UI items on a screen.

FIGURE 5-2: Virtual keyboards can adapt to the user’s needs.

Book 7 Chapter 6

FIGURE 6-1: Visual scripting lets you create a program by connecting nodes in a...

Book 7 Chapter 7

FIGURE 7-1: A virtual machine lets a program run on multiple operating systems.

Guide

Cover

Title Page

Copyright

Table of Contents

Begin Reading

Index

About the Author

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Introduction

If you enjoy using a computer, you may have even more fun learning to control a computer by writing your own programs. To learn how to program a computer, you need to:

Understand that computer programming is nothing more than problem solving.

Before you even think about writing a program, you need to know what problem you want your program to solve and how it will solve it.

Learn the basic ideas behind computer programming that work with all programming languages on any computer.

Although programming a Windows computer is different from programming a Mac, a smartphone, a smart watch, or a super computer, the general principles remain the same. By learning what these common programming principles are and why they exist, you can learn different ways to tell a computer what to do, step-by-step.

Learn a specific programming language.

A programming language represents just one way to express your ideas in a language that the computer can understand. By combining your knowledge of a programming language with programming principles and the type of problem you want the computer to solve, you can create your own computer programs for fun or profit.

About This Book

If you have any interest in programming but don’t know where to start, this book can give you a nudge in the right direction. You won’t learn how to write programs in a specific programming language, but you’ll learn the basics of computer programming so you’ll have no trouble learning more on your own.

If you already know something about programming, this book can still help you learn more by introducing you to the variety of programming languages available and make it easy for you to pick up different programming languages quickly. The more you understand the advantages and disadvantages of different programming languages, the better you’ll be able to choose the language that’s best suited for a particular task.

Whether you’re a novice or an intermediate programmer, you’ll find this book can work as a tutorial to teach you more and as a reference to help refresh your memory on programming topics you may not normally use every day. This book won’t turn you into an expert overnight, but it will open the doors to more information about programming than you may have ever known even existed.

This book is a reference — you don’t need to read the chapters in order from front cover to back and you don’t have to commit anything you read here to memory. Also, sidebars (text in gray boxes) and anything marked with the Technical Stuff icon are skippable.

Finally, within this book, you may note that some web addresses break across two lines of text. If you’re reading this book in print and want to visit one of these web pages, simply key in the web address exactly as it’s noted in the text, pretending as though the line break doesn’t exist. If you’re reading this as an e-book, you’ve got it easy — just click the web address to be taken directly to the web page.

Foolish Assumptions

When writing this book, I made two assumptions about you, the reader:

You may have no experience in computer programming or a limited amount of experience, but you’re eager to learn.

You have a computer (whether it’s the latest model on the market or simply an older model that still works). Ideally, your computer can connect to the Internet.

That’s it! As long as you have a computer and the desire to learn, you have everything you need to learn computer programming.

Icons Used in This Book

Icons highlight important or useful information that you may want to know about. Here’s a guide to the icons:

The Tip icon highlights information that can save you time or make it easier for you to do something.

The Remember icon emphasizes information that’s so important you should commit it to memory.

Look out! The Warning icon highlights something dangerous that you need to avoid before making an irreversible mistake that could make you curse your computer forever.

The Technical Stuff icon highlights interesting technical information that you can safely ignore, but which may provide additional background about programming a computer.

Beyond the Book

In addition to what you’re reading right now, this product also comes with a free access-anywhere Cheat Sheet that summarizes different types of programming principles, common ways to store and organize data, and lists of suggested software to use. To get this Cheat Sheet, simply go to www.dummies.com and type Beginning Programming All-in-One For Dummies Cheat Sheet in the Search box.

Where to Go from Here

You can use this book as a tutorial or a reference. Although you can just flip through this book to find the information you need, programming novices should start with Book 1 before tackling any other books. After you understand the basics of programming from Book 1, you can freely jump around to read only the information that interests you.

Programming is more than learning a particular programming language or even knowing how to program a particular type of computer. Basically, programming is about tackling difficult problems and breaking them down into smaller problems until you ultimately solve one much bigger problem. If you like the idea of solving problems, this may be the perfect book to introduce you to the wonderful world of computer programming!

Book 1

Getting Started with Programming

Contents at a Glance

Chapter 1: Getting Started Programming a Computer

How Computer Programming Works

The History of Computer Programming

Figuring Out Programming

Chapter 2: Different Methods for Writing Programs

Spaghetti Programming

Structured Programming

Event-Driven Programming

Object-Oriented Programming

Using Protocol-Oriented Programming

Design Patterns

Chapter 3: Types of Programming Languages

Your First Language

Curly-Bracket Languages

Artificial Intelligence Languages

Scripting Languages

Database Programming Languages

Comparing Programming Languages

Chapter 4: Programming Tools

Choosing a Compiler

Finding an Interpreter

Compiling to a Virtual Machine

Writing a Program with an Editor

Fixing a Program with a Debugger

Saving Time with Third-Party Components

Optimizing a Program with a Profiler

Managing Source Code

Creating a Help File

Installing a Program

Dissecting Programs with a Disassembler

Chapter 1

Getting Started Programming a Computer

IN THIS CHAPTER

Understanding how computer programming works

Diving into the history of computer programming

Discovering programming

Believe it or not, if you can write a recipe on an index card, you can program a computer! At the simplest level, computer programming is nothing more than writing instructions for a computer to follow, step-by-step. The most important part of programming isn’t knowing how to write a program or how to use a particular programming language, but knowing what to create in the first place.

Some of the most popular and useful computer programs were created by people who didn’t have any formal training in math or computer science. Dan Bricklin invented the spreadsheet while studying for his MBA at Harvard. Scott Cook, who worked in marketing and product development at Procter & Gamble, created the popular money-management program Quicken after hearing his wife complain about the tedium of paying bills. Nineteen-year-old Shawn Fanning created Napster, the first peer-to-peer file-sharing network, after hearing a friend complain about the difficulty of finding his favorite songs on the Internet. Game developer Dona Bailey wanted to create a video game that would appeal to both men and women; as the only woman working at Atari’s coin-op division, she created the video game Centipede, which became Atari’s second best-selling coin-op game.

The point is that anyone can figure out how to program a computer. What’s more important than knowing how to program a computer is knowing what to do with your programming skills. As Albert Einstein said, “Imagination is more important than knowledge.” After you have an idea for a program, you can use programming to turn your idea into reality.

How Computer Programming Works

Computer programming is nothing more than problem solving. Every program is designed to solve a specific problem. The more universal the problem (calculating formulas in a spreadsheet, managing your money, searching for music files over the Internet, or keeping people amused playing a game creating virtual buildings), the more useful and popular the program will be.

Identifying the problem

Before you even touch a computer, identify the specific problem you want the computer to solve. For example, spreadsheets eliminate the tedium of writing and calculating formulas manually. Word processors make editing and formatting text fast and easy. Even video games solve the problem of challenging people with puzzles, obstacles, and battles.

Although the most popular programs solve universal problems, literally thousands of programs are designed to solve specific problems in niche markets, such as hotel reservation software, construction billing and invoice management programs, and dental office management programs. If you can identify a problem that a computer can solve or simplify, you have an idea for a computer program.

You must know exactly what you want your program to do before you start designing and writing it. One of the most common reasons programs fail is because the program doesn’t solve the right problem that people really need.

THE FBI’S $170 MILLION FLOP

The Federal Bureau of Investigation (FBI) had a problem. It had so much information, stored on paper, scattered among so many agents around the country that finding and using this information was nearly impossible. One agent might have vital information that could help a second agent crack a case, but unless those two agents knew what each other had, that information might as well never have existed in the first place.

So, the FBI had a bright idea: Create a computer program that would allow agents to store and share information through the computer. Several years and $170 million later, the FBI had its program, dubbed Virtual Case File, which consisted of more than 700,000 lines of error-prone commands that never even worked. Rather than try to salvage the project, the FBI decided it was easier just to cancel the whole thing and basically flush 170 million taxpayer dollars down the drain.

What went wrong? Although many factors contributed to the project’s failure, one reason stands out in particular: According to an audit of the program conducted by the U.S. Department of Justice, a prime cause for failure was “poorly defined and slowly evolving design requirements.” In other words, the FBI never knew exactly what it wanted the program to do.

How can you aim at a target if you don’t know what it is? You can’t. Or you can try, just as long as you spend $170 million to discover that if you don’t know what you want, you’re probably never going to get it.

Defining the steps

After you know what you want your program to do, you need to define all the steps that tell the computer how to solve that particular problem. The exact steps that define how the program should work is called an algorithm. An algorithm simply defines one of many possible ways to solve a problem.

There’s no single “best” algorithm for writing a program. The same program can be written in a million different ways, so the “best” way to write a program is any way that creates a useful, working, and reliable program as quickly as possible. Anything else is irrelevant.

Knowing what you want the computer to do is the first step. The second step is telling the computer how to do it, which is what makes programming so difficult. The more you want the computer to do, the more instructions you need to give the computer.

Think of a computer program as a recipe. It’s easy to write a recipe for making spaghetti. Just boil water, throw in the noodles until they’re soft, drain, and serve. Now consider a recipe for making butternut squash and potato pie with tomato, mint, and sheep’s milk cheese from Crete. Not as simple as boiling water to make spaghetti, is it?

The same principle holds true for computer programming. The simpler the task, the simpler the program. The harder the task, the bigger and more complicated the program. If you just want a program that displays today’s date on the screen, you won’t need to write many instructions. If you want to write a program that simulates flying a space shuttle in orbit around the Earth, you’ll need to write a lot more instructions.

The more instructions you need to write, the longer it takes and the more likely you’ll make a mistake somewhere along the way.

Ultimately, programming boils down to two tasks:

Identifying exactly what you want the computer to do

Writing step-by-step instructions that tell the computer how to do what you want

The History of Computer Programming

Although computer programming may seem like a recent invention, the idea behind writing instructions for a machine to follow has been around for over a century. One of the earliest designs for a programmable machine (in other words, a computer) came from a man named Charles Babbage way back in 1834.

That was the year Charles Babbage proposed building a mechanical, steam-driven machine dubbed the Analytical Engine. Unlike the simple calculating machines of that time that could perform only a single function, Charles Babbage’s Analytical Engine could perform a variety of tasks, depending on the instructions fed into the machine through a series of punched cards. By changing the number and type of instructions (punch cards) fed into the machine, anyone could reprogram the Analytical Engine to make it solve different problems.

The idea of a programmable machine caught the attention of Ada Lovelace, a mathematician and daughter of the poet Lord Byron. Sensing the potential of a programmable machine, Ada wrote a program to make the Analytical Engine calculate and print a sequence of numbers known as the Bernoulli numbers.

Because of her work with the Analytical Engine, Ada Lovelace is considered to be the world’s first computer programmer. In her honor, the Department of Defense named the Ada programming language after Ada Lovelace. Nvidia named a family of graphics cards after Ada Lovelace as well.

Although Charles Babbage never finished building his Analytical Engine, his steam-driven mechanical machine bears a striking similarity to today’s computers. To make the Analytical Engine solve a different problem, you just had to feed it different instructions. To make a modern computer solve a different problem, you just have to run a different program.

Over a century later, the first true computer appeared in 1943 when the U.S. Army funded a computer to calculate artillery trajectories. This computer, dubbed ENIAC (short for Electronic Numerical Integrator and Computer), consisted of vacuum tubes, switches, and cables. To give ENIAC instructions, you had to physically flip its different switches and rearrange its cables.

The first ENIAC programmers were all women.

Physically rearranging cables and switches to reprogram a computer worked, but it was tedious and clumsy. Instead of having to physically rearrange the computer’s wiring, computer scientists decided it would be easier if they could leave the computer physically the same but just rearrange the type of instructions given to it. By giving the computer different instructions, they could make the computer behave in different ways.

In the old days, computers filled entire rooms and cost millions of dollars. Today, computers have shrunk so far in size that they’re essentially nothing more than a little silicon wafer, about the size of a coin.

A processor is essentially an entire computer. To tell the processor what to do, you have to give it instructions written in machine language (a language that the processor can understand).

To make faster computers, engineers combine multiple processors (called cores) together and make them work as a team. So, instead of having a single processor in your computer, the latest computers have multiple processors or cores working together.

Talking to a processor in machine language

To understand how machine language works, you have to understand how processors work. Basically, a processor consists of nothing more than millions of tiny switches that can turn on or off. By turning certain switches on or off, you can make the processor do something useful.

Instead of physically turning switches on or off, machine language lets you turn a processor’s switches on or off by using two numbers: 1 (one) and 0 (zero), where the number 1 means “turn a switch on” and the number 0 means “turn a switch off.” So a typical machine language instruction might look like this:

1011 0000 0110 0001