C For Dummies, 2nd Edition

while (dead_horse) beat (): If you’re like most people, the above seems like nonsense. Actually, it’s computer sense—C programming. After digesting C For Dummies, 2 nd Edition, you’ll understand it. C programs are fast, concise and versatile. They let you boss your computer around for a change. So turn on your computer, get a free compiler and editor (the book tells you where), pull up a chair, and get going. You won’t have to go far (page 13) to find your first program example. You’ll do short, totally manageable, hands-on exercises to help you make sense of: All 32 keywords in the C language (that’s right—just 32 words) The functions—several dozen of them Terms like printf(), scanf(), gets (), and puts () String variables, numeric variables, and constants Looping and implementation Floating-point values In case those terms are almost as intimidating as the idea of programming, be reassured that C For Dummies was written by Dan Gookin, bestselling author of DOS For Dummies , the book that started the whole library. So instead of using expletives and getting headaches, you’ll be using newly acquired skills and getting occasional chuckles as you discover how to: Design and develop programs Add comments (like post-it-notes to yourself) as you go Link code to create executable programs Debug and deploy your programs Use lint, a common tool to examine and optimize your code A helpful, tear-out cheat sheet is a quick reference for comparison symbols, conversion characters, mathematical doodads, C numeric data types, and more. C For Dummies takes the mystery out of programming and gets you into it quickly and painlessly. C For Dummies, 2nd Edition 5 About the Author 7 Contents at a Glance 9 Table of Contents 11 Introduction 21 “ What Will Understanding C Do for Me?” 21 About This Here Dummies Approach 22 How to Work the Examples in This Book 22 Foolish Assumptions 23 Icons Used in This Book 23 What’s New with This Edition? 24 Final Thots 24 Part I: Introduction to C Programming 27 Chapter 1: Up from the Primordial C 29 An Extremely Short and Cheap History of the C Language 29 The C Development Cycle 31 From Text File to Program 31 Save It! Compile and Link It! Run It! 36 Chapter 2: C of Sorrow, C of Woe 39 The Required Woes of Editing and Recompiling 39 Dealing with the Heartbreak of Errors 42 Chapter 3: C Straight 49 The Big Picture 49 C Language Pieces’ Parts 50 The C Language Itself — the Keywords 52 Other C Language Components 54 Pop Quiz! 55 The Helpful RULES Program 56 Chapter 4: C What I/O 59 Introduce Yourself to Mr. Computer 59 More on 61 Is Pronounced “ Scan-Eff” 69 Chapter 5: To C or Not to C 75 Adding Comments 75 Comment Styles of the Nerdy and Not-Quite-Yet-Nerdy 78 Using Comments to Disable 81 The Perils of “ Nested” Comments 82 Chapter 6: C More I/O with gets ( ) and puts ( ) 85 The More I Want, the More I gets ( ) 85 The Virtues of puts ( ) 87 Part II: Run and Scream from Variables and Math 93 Chapter 7: A + B = C 95 The Ever-Changing Variable 95 Welcome to the Cold World of Numeric Variables 97 A Wee Bit o’ Math 106 Chapter 8: Charting Unknown Cs with Variables 113 Cussing, Discussing, and Declaring Variables 113 Constants and Variables 121 Chapter 9: How to C Numbers 127 There Are Numbers, and Then There Are Numbers 127 How to Make a Number Float 133 Bigger than the Float, It’s a Double! 138 Formatting Your Zeroes and Decimal Places 139 Chapter 10: Cook That C Variable Charred, Please 141 The Other Kind of Variable Type, the 141 Reading and Writing Single Characters 145 Character Variables As Values 148 Part III: Giving Your Programs the Ability to Run Amok 151 Chapter 11: C More Math and the Sacred Order of Precedence 153 An All-Too-Brief Review of the Basic C Mathematical Operators 153 The Delicate Art of Incrementation ( Or, “ Just Add One to It”) 157 The Sacred Order of Precedence 161 Chapter 12: C the Mighty if Command 167 If Only. . . . 167 If It Isn’t True, What Else? 177 Chapter 13: What If C==C? 185 The World of if without Values 185 Using the if Keyword to Compare Two Strings 194 Chapter 14: Iffy C Logic 195 Exposing Flaws in Logic 195 If, And, Or, But 197 Chapter 15: C You Again 205 For Going Loopy 205 I’m Bustin’ Outta Here! 213 Chapter 16: C the Loop, C the Loop++ 221 The Art of Incrementation 221 The Mysterious Practice of Decrementation 224 More Incrementation Madness 229 Chapter 17: C You in a While Loop 235 The Lowdown on while Loops 235 Not to Beat a Dead Horse or Anything. . . . 243 Chapter 18: Do C While You Sleep 245 The Down-Low on Upside-Down do-while Loops 245 Nested Loops and Other Bird-Brained Concepts 251 Break the Brave and Continue the Fool 255 Chapter 19: Switch Case, or, From ‘ C’ to Shining ‘ c’ 259 The Sneaky switch-case Loops 259 The switch-case Solution to the LOBBY Program 261 The Old switch-case Trick 263 The Special Relationship between while and switch-case 268 Part IV: C Level 271 Chapter 20: Writing That First Function 273 Meet Mr. Function 273 Prototyping Your Functions 278 The Tao of Functions 282 Chapter 21: Contending with Variables in Functions 285 Bombs Away with the BOMBER Program! 285 How We Can All Share and Love with Global Variables 289 Chapter 22: Functions That Actually Funct 295 Marching a Value Off to a Function 295 Sending More than One Value to a Function 300 Functions That Return Stuff 302 No Need to Bother with This C Language Trivia If You’re in a Hurry 309 Chapter 23: The Stuff That Comes First 313 Please Don’t Leave Me Out! 314 What the #defines Are Up To 322 Avoiding the Topic of Macros 323 Chapter 24: The printf( ) Chapter 325 A Quick Review of printf( ) 325 The Old Displaying-Text-with-printf( ) Routine 326 The printf( ) Escape Sequences 326 The Complex printf( ) Format 330 The printf( )Conversion Characters 331 Chapter 25: Math Madness! 333 More on Math 333 Strange Math? You Got It! 339 Something Really Odd to End Your Day 340 Chapter 26: The Old Random-Number Function 345 On Being Random 345 The Diabolical Dr. Modulus 353 Rolling the Dice with the Final RANDOM Program 355 Part V: The Part of Tens 357 Chapter 27: Ten More Things You Need to Know about the C Language 359 Arrays 359 Strings 360 Structures 361 Pointers 363 Linked Lists 363 Binary Operators 364 Interacting with the Command Line 365 Disk Access 365 Interacting with the Operating System 365 Building Big Programs 366 Chapter 28: Ten Tips for the Budding Programmer 367 Use the Command-Line History 367 Keep Your Editor Open in Another Window 368 Use a Context-Colored Text Editor 368 Know the Line-Number Commands in Your Editor 369 Keep a Command Prompt Window Open If You’re Using the IDE 370 Know a Few Handy Command-Prompt Commands 370 Carefully Name Your Variables 371 Know Your Post-and Pre-Incrementing and Decrementing Riddles 371 Breaking Out of a Loop 372 Chapter 29: Ten Ways to Solve Your Own Programming Problems 373 Work on One Thing at a Time 374 Break Up Your Code 374 Simplify 375 Talk through the Program 375 Set Breakpoints 376 Monitor Your Variables 376 Document Your Work 376 Use Debugging Tools 377 Use a C Optimizer 377 Read More Books! 378 Appendix A: The Stuff You Need to Know before You Read All the Other Stuff in This Book 379 Setting Things Up 379 Making Programs 383 Appendix B: ASCII Table 391 Index 397