PROBLEM SOLVING SEVENTH EDITION WALTER SAVITCH UNIVERSITY OF CALIFORNIA, SAN DIEGO CONTRIBUTOR KENRICK MOCK UNIVERSITY OF ALASKA, ANCHORAGE PEARSON

Transcription

1 PROBLEM SOLVING WITH SEVENTH EDITION WALTER SAVITCH UNIVERSITY OF CALIFORNIA, SAN DIEGO CONTRIBUTOR KENRICK MOCK UNIVERSITY OF ALASKA, ANCHORAGE PEARSON Addison Wesley Boston San Francisco New York London Toronto Sydney Tokyo Singapore Madrid Mexico City Munich Paris Cape Town Hong Kong Montreal

2 Contents TABLE OF LOCATION OF VIDEO NOTES Inside front cover Chapter 1 Introduction to Computers and C++ Programming COMPUTER SYSTEMS 32 Hardware 32 Software 37 High-Level Languages 38 Compilers 39 History Note PROGRAMMING AND PROBLEM-SOLVING 42 Algorithms 42 Program Design 45 Object-Oriented Programming 47 The Software Life Cycle INTRODUCTION TO C++ 49 Origins of the C++ Language 49 A Sample C++ Program 50 Pitfall: Using the Wrong Slash in \n 54 Programming Tip: Input and Output Syntax 54 Layout of a Simple C++ Program 54 Pitfall: Putting a Space before the include File Name 56 Compiling and Running a C++ Program 57 Programming Tip: Getting Your Program to Run TESTING AND DEBUGGING 60 Kinds of Program Errors 60 Pitfall: Assuming Your Program Is Correct 61 15

3 16 CONTENTS Chapter Summary 62 Answers to Self-Test Exercises 63 Programming Projects 66 Chapter 2 C++ Basics VARIABLES AND ASSIGNMENTS 70 Variables 70 Names: Identifiers 72 Variable Declarations 74 Assignment Statements 75 Pitfall: Uninitialized Variables 77 Programming Tip: Use Meaningful Names INPUT AND OUTPUT 80 Output Using cout 80 Include Directives and Namespaces 82 Escape Sequences 83 Programming Tip: End Each Program with a \n or endl 85 Formatting for Numbers with a Decimal Point 85 Input Using ein 86 Designing Input and Output 88 Programming Tip: Line Breaks in I/O DATA TYPES AND EXPRESSIONS 90 The Types int and double 90 Other Number Types 92 The Type char 93 The Type boo I 94 Introduction to the Class string 95 Type Compatibilities 96 Arithmetic Operators and Expressions 99 Pitfall: Whole Numbers in Division 101 More Assignment Statements SIMPLE FLOW OF CONTROL 104 A Simple Branching Mechanism 104 Pitfall: Strings of Inequalities 110 Pitfall: Using = in place of == 111 Compound Statements 112 Simple Loop Mechanisms 114

4 Increment and Decrement Operators 117 Programming Example: ChargeCard Balance 119 Pitfall: Infinite Loops PROGRAM STYLE 123 Indenting 123 Comments 124 Naming Constants 126 Chapter Summary 128 Answers to Self-Test Exercises 129 Programming Projects 134 Chapter 3 More Flow of Control USING BOOLEAN EXPRESSIONS 142 Evaluating Boolean Expressions 142 Pitfall: Boolean Expressions Convert to int Values 146 Enumeration Types (Optional) MULTIWAY BRANCHES 150 Nested Statements 150 Programming Tip: Use Braces in Nested Statements 1.51 Multiway if-else Statements 153 Programming Example: State Income Tax 155 The switch Statement 159 Pitfall: Forgetting a break in a switch Statement 163 Using switch Statements for Menus 164 Blocks 164 Pitfall: Inadvertent Local Variables MORE ABOUT C++ LOOP STATEMENTS 170 The while Statements Reviewed 171 Increment and Decrement Operators Revisited 172 The for Statement 175 Pitfall: Extra Semicolon in a for Statement 180 What Kind of Loop to Use 181 Pitfall: Uninitialized Variables and Infinite Loops 183 The break Statement 183 Pitfall: The break Statement in Nested Loops 185

5 18 CONTENTS 3.4 DESIGNING LOOPS 186 Loops for Sums and Products 186 Ending a Loop 187 Nested Loops 191 Debugging Loops 193 Chapter Summary 196 Answers to Self-Test Exercises 197 Programming Projects 203 Chapter 4 Procedural Abstraction and Functions That Return a Value TOP-DOWN DESIGN PREDEFINED FUNCTIONS 213 Using Predefined Functions 213 Type Casting 218 Older Form of Type Casting 220 Pitfall: Integer Division Drops the Fractional Part PROGRAMMER-DEFINED FUNCTIONS 222 Function Definitions 222 Functions That Return a Boolean Value 226 Alternate Form for Function Declarations 229 Pitfall: Arguments in the Wrong Order 229 Function Definition-Syntax Summary 231 More About Placement of Function Definitions 232 Programming Tip: Use Function Calls in Branching Statements PROCEDURAL ABSTRACTION 234 The Black Box Analogy 234 Programming Tip: Choosing Formal Parameter Names 236 Programming Tip: Nested Loops 238 Case Study: Buying Pizza 241 Programming Tip: Use Pseudocode LOCAL VARIABLES 248 The Small Program Analogy 248 Programming Example: Experimental Pea Patch 250 Global Constants and Global Variables 251

6 Call-by-Value Formal Parameters Are Local Variables 254 Namespaces Revisited 256 Programming Example: The Factorial Function OVERLOADING FUNCTION NAMES 260 Introduction to Overloading 261 Programming Example: Revised Pizza-Buying Program 263 Automatic Type Conversion 266 Chapter Summary 269 Answers to Self-Test Exercises 269 Programming Projects 274 Chapter 5 Functions for All Subtasks void FUNCTIONS 282 Definitions of void Functions 282 Programming Example: Converting Temperatures 285 return Statements in void Functions CALL-BY-REFERENCE PARAMETERS 289 A First View of Call-by-Reference 289 Call-by-Reference in Detail 292 Programming Example: The swap_values Function 296 Mixed Parameter Lists 298 Programming Tip: What Kind of Parameter to Use 298 Pitfall: Inadvertent Local Variables USING PROCEDURAL ABSTRACTION 302 Functions Calling Functions 303 Preconditions and Postconditions 303 Case Study: Supermarket Pricing TESTING AND DEBUGGING FUNCTIONS 312 Stubs and Drivers GENERAL DEBUGGING TECHNIQUES 317 Keep an Open Mind 317 Check Common Errors 318 Localize the Error 318 The assert macro 321

7 Chapter Summary 322 Answers to Self-Test Exercises 323 Programming Projects 327 Chapter 6 I/O Streams as an Introduction to Objects and Classes STREAMS AND BASIC FILE I/O 336 Why Use Files for I/O? 337 File I/O 338 Introduction to Classes and Objects 342 Programming Tip: Check Whether a File Was Opened Successfully 343 Techniques for File I/O 346 Appending to a File (Optional) 350 File Names as Input (Optional) TOOLS FOR STREAM I/O 353 Formatting Output with Stream Functions 353 Manipulators 358 Streams as Arguments to Functions 362 Programming Tip: Checking for the End of a File 362 A Note on Namespaces 366 Programming Example: Cleaning Up a File Format CHARACTER I/O 368 The Member Functions get and put 369 The putback Member Function (Optional) 372 Programming Example: Checking Input 373 Pitfall: Unexpected '\n' in Input 376 The eof Member Function 379 Programming Example: Editing a Text File 382 Predefined Character Functions 382 Pitfall: toupper and tolower Return Values 385 Chapter Summary 387 Answers to Self-Test Exercises 389 Programming Projects 394

8 Chapter 7 Arrays INTRODUCTION TO ARRAYS 406 Declaring and Referencing Arrays 406 Programming Tip: Use for Loops with Arrays 408 Pitfall: Array Indexes Always Start with Zero 408 Programming Tip: Use a Defined Constant for the Size of an Array Arrays in Memory 410 Pitfall: Array Index Out of Range 411 Initializing Arrays ARRAYS IN FUNCTIONS 415 Indexed Variables as Function Arguments 415 Entire Arrays as Function Arguments 418 The const Parameter Modifier 421 Pitfall: Inconsistent Use of const Parameters 423 Functions That Return an Array 424 Case Study: Production Graph PROGRAMMING WITH ARRAYS 438 Partially Filled Arrays 438 Programming Tip: Do Not Skimp on Formal Parameters 441 Programming Example: Searching an Array 442 Programming Example: Sorting an Array MULTIDIMENSIONAL ARRAYS 449 Multidimensional Array Basics 450 Multidimensional Array Parameters 450 Programming Example: Two-Dimensional Grading Program 452 Pitfall: Using Commas Between Array Indexes 457 Chapter Summary 457 Answers to Self-Test Exercises 458 Programming Projects 463 Chapter 8 Strings and Vectors AN ARRAY TYPE FOR STRINGS 477 C-String Values and C-String Variables 477 Pitfall: Using = and == with С Strings 481

9 Other Functions in <cstring> 483 C-String Input and Output 487 C-String-to-Number Conversions and Robust Input THE STANDARD string CLASS 495 Introduction to the Standard Class string 495 I/O with the Class string 498 Programming Tip: More Versions of getline 502 Pitfall: Mixing ein» variable; and getline 502 String Processing with the Class string 504 Programming Example: Palindrome Testing 506 Converting between string Objects and С Strings VECTORS 512 Vector Basics 512 Pitfall: Using Square Brackets Beyond the Vector Size 514 Programming Tip: Vector Assignment Is Well Behaved 516 Efficiency Issues 517 Chapter Summary 518 Answers to Self-Test Exercises 519 Programming Projects 521 Chapter 9 Pointers and Dynamic Arrays POINTERS 530 Pointer Variables 531 Basic Memory Management 538 Pitfall: Dangling Pointers 539 Static Variables and Automatic Variables 540 Programming Tip: Define Pointer Types DYNAMIC ARRAYS 543 Array Variables and Pointer Variables 543 Creating and Using Dynamic Arrays 543 Pointer Arithmetic (Optional) 549 Multidimensional Dynamic Arrays (Optional) 551 Chapter Summary 553 Answers to Self-Test Exercises 553 Programming Projects 554

10 Chapter 10 Defining Classes STRUCTURES 560 Structures for Diverse Data 560 Pitfall: Forgetting a Semicolon in a Structure Definition 565 Structures as Function Arguments 566 Programming Tip: Use Hierarchical Structures 567 Initializing Structures CLASSES 572 Defining Classes and Member Functions 572 Public and Private Members 577 Programming Tip: Make All Member Variables Private 585 Programming Tip: Define Accessor and Mutator Functions 585 Programming Tip: Use the Assignment Operator with Objects 587 Programming Example: BankAccount Class Version Summary of Some Properties of Classes 592 Constructors for Initialization 594 Programming Tip: Always Include a Default Constructor 602 Pitfall: Constructors with No Arguments ABSTRACT DATA TYPES 605 Classes to Produce Abstract Data Types 606 Programming Example: Alternative Implementation of a Class INTRODUCTION TO INHERITANCE 614 Inheritance Among Stream Classes 615 Programming Example: Another new.line Function 618 Default Arguments for Functions (Optional) 619 Defining Derived Classes 621 Chapter Summary 624 Answers to Self-Test Exercises 625 Programming Projects 633 Chapter 11 Friends, Overloaded Operators, and Arrays in Classes FRIEND FUNCTIONS 640 Programming Example: An Equality Function 640 Friend Functions 644

11 24 CONTENTS Programming Tip: Define Both Accessor Functions and Friend Functions 646 Programming Tip: Use Both Member and Nonmember Functions 648 Programming Example: Money Class (Version 1) 648 Implementation of digi.t_to_i.nt (Optional) 655 Pitfall: Leading Zeros in Number Constants 656 The const Parameter Modifier 658 Pitfall: Inconsistent Use of const OVERLOADING OPERATORS 663 Overloading Operators 664 Constructors for Automatic Type Conversion 668 Overloading Unary Operators 670 Overloading» and « ARRAYS AND CLASSES 681 Arrays of Classes 681 Arrays as Class Members 685 Programming Example: A Class for a Partially Filled Array CLASSES AND DYNAMIC ARRAYS 689 Programming Example: A String Variable Class 689 Destructors 693 Pitfall: Pointers as Call-by-Value Parameters 695 Copy Constructors 697 Overloading the Assignment Operator 702 Chapter Summary 705 Answers to Self-Test Exercises 706 Programming Projects 716 Chapter 12 Separate Compilation and Namespaces SEPARATE COMPILATION 726 ADTs Reviewed 727 Case Study: DigitalTime A Class Compiled Separately 728 Using #ifndef 737 Programming Tip: Defining Other Libraries 740

12 12.2 NAMESPACES 742 Namespaces and using Directives 742 Creating a Namespace 744 Qualifying Names 747 A Subtle Point About Namespaces (Optional) 748 Unnamed Namespaces 749 Programming Tip: Choosing a Name for a Namespace 752 Pitfall: Confusing the Global Namespace and the Unnamed Namespace 754 Chapter Summary 757 Answers to Self-Test Exercises 757 Programming Projects 759 Chapter 13 Pointers and Linked Lists NODES AND LINKED LISTS 764 Nodes 764 Linked Lists 770 Inserting a Node at the Head of a List 771 Pitfall: Losing Nodes 774 Searching a Linked List 775 Pointers as Iterators 779 Inserting and Removing Nodes Inside a List 779 Pitfall: Using the Assignment Operator with Dynamic Data Structures 782 Variations on Linked Lists 784 Linked Lists of Classes STACKS AND QUEUES 790 Stacks 790 Programming Example: A Stack Class 791 Queues 796 Programming Example: A Queue Class 797 Chapter Summary 801 Answers to Self-Test Exercises 802 Programming Projects 805

13 Chapter 14 Recursion RECURSIVE FUNCTIONS FOR TASKS 813 Case Study: Vertical Numbers 813 A Closer Look at Recursion 820 Pitfall: Infinite Recursion 821 Stacks for Recursion 823 Pitfall: Stack Overflow 824 Recursion Versus Iteration RECURSIVE FUNCTIONS FOR VALUES 826 General Form for a Recursive Function That Returns a Value 826 Programming Example: Another Powers Function THINKING RECURSIVELY 831 Recursive Design Techniques 831 Case Study: Binary Search An Example of Recursive Thinking 833 Programming Example: A Recursive Member Function 840 Chapter Summary 845 Answers to Self-Test Exercises 845 Programming Projects 850 Chapter 15 Inheritance INHERITANCE BASICS 856 Derived Classes 857 Constructors in Derived Classes 865 Pitfall: Use of Private Member Variables from the Base Class 868 Pitfall: Private Member Functions Are Effectively Not Inherited 870 The protected Qualifier 870 Redefinition of Member Functions 873 Redefining Versus Overloading 877 Access to a Redefined Base Function INHERITANCE DETAILS 879 Functions That Are Not Inherited 880 Assignment Operators and Copy Constructors in Derived Classes 880 Destructors in Derived Classes 881

14 15.3 POLYMORPHISM 883 Late Binding 883 Virtual Functions in C Virtual Functions and Extended Type Compatibility 890 Pitfall: The Slicing Problem 894 Pitfall: Not Using Virtual Member Functions 894 Pitfall: Attempting to Compile Class Definitions Without Definitions for Every Virtual Member Function 895 Programming Tip: Make Destructors Virtual 896 Chapter Summary 897 Answers to Self-Test Exercises 898 Programming Projects 902 Chapter 16 Exception Handling EXCEPTION-HANDLING BASICS 913 A Toy Example of Exception Handling 913 Defining Your Own Exception Classes 922 Multiple Throws and Catches 922 Pitfall: Catch the More Specific Exception First 926 Programming Tip: Exception Classes Can Be Trivial 927 Throwing an Exception in a Function 928 Exception Specification 928 Pitfall: Exception Specification in Derived Classes PROGRAMMING TECHNIQUES FOR EXCEPTION HANDLING 933 When to Throw an Exception 933 Pitfall: Uncaught Exceptions 935 Pitfall: Nested try-catch Blocks 935 Pitfall: Overuse of Exceptions 935 Exception Class Hierarchies 936 Testing for Available Memory 936 Rethrowing an Exception 937 Chapter Summary 937 Answers to Self-Test Exercises 937 Programming Projects 939

15 Chapter 17 Templates TEMPLATES FOR ALGORITHM ABSTRACTION 944 Templates for Functions 945 Pitfall: Compiler Complications 949 Programming Example: A Generic Sorting Function 951 Programming Tip: How to Define Templates 955 Pitfall: Using a Template with an Inappropriate Type TEMPLATES FOR DATA ABSTRACTION 957 Syntax for Class Templates 957 Programming Example: An Array Class 960 Chapter Summary 966 Answers to Self-Test Exercises 966 Programming Projects 969 Chapter 18 Standard Template Library ITERATORS 975 using Declarations 975 Iterator Basics 976 Pitfall: Compiler Problems 981 Kinds of Iterators 982 Constant and Mutable Iterators 986 Reverse Iterators 987 Other Kinds of Iterators CONTAINERS 990 Sequential Containers 990 Pitfall: Iterators and Removing Elements 995 Programming Tip: Type Definitions in Containers 995 Container Adapters stack and queue 996 Associative Containers set and map 1000 Efficiency GENERIC ALGORITHMS 1007 Running Times and Big-0 Notation 1008 Container Access Running Times 1012 Nonmodifying Sequence Algorithms 1013 Container Modifying Algorithms 1019

16 CONTENTS 29 Set Algorithms 1019 Sorting Algorithms 1021 Chapter Summary 1021 Answers to Self-Test Exercises 1022 Programming Projects 1024 APPENDICES 1 C++ Keywords Precedence of Operators The ASCII Character Set Some Library Functions Inline Functions Overloading the Array Index Square Brackets The this Pointer Overloading Operators as Member Operators 1047 INDEX 1049