Programming Languages Chapter 2 Programming From Problem Analysis Program Design Eighth Edition Basic Elements Guide

Unlock access to all the studying documents.

View Full Document

C++ Programming: From Problem Analysis to Program Design, Eighth Edition 2-1

Chapter 2

Basic Elements of C++

A Guide to this Instructor’s Manual:

We have designed this Instructor’s Manual to supplement and enhance your teaching

experience through classroom activities and a cohesive chapter summary.

At a Glance

Instructor’s Manual Table of Contents

• Overview

• Objectives

• Teaching Tips

• Quick Quizzes

• Class Discussion Topics

• Additional Projects

• Additional Resources

• Key Terms

C++ Programming: From Problem Analysis to Program Design, Eighth Edition 2-2

Lecture Notes

Overview

Chapter 2 teaches your students the basics of C++. Learning a programming language is

similar to learning to be a chef or learning to play a musical instrument. All three

require direct interaction with the tools; in other words, you cannot become proficient

by simply reading books on the topics. In this chapter, your students will begin

acquiring a fundamental knowledge of C++ by learning about data types, functions,

identifiers, assignment statements, arithmetic operations, and input/output operations.

They will then write and test programs using these concepts to verify their knowledge

of the material.

Objectives

In this chapter, the student will:

• Become familiar with the basic components of a C++ program, including functions,

special symbols, and identifiers

• Explore simple data types

• Discover how to use arithmetic operators

• Examine how a program evaluates arithmetic expressions

• Become familiar with the string data type

• Learn what an assignment statement is and what it does

• Learn about variable declaration

• Discover how to input data into memory using input statements

• Become familiar with the use of increment and decrement operators

• Examine ways to output results using output statements

• Learn how to use preprocessor directives and why they are necessary

• Learn how to debug syntax errors

• Explore how to properly structure a program, including using comments to document a

program

• Become familiar with compound statements

• Learn how to write a C++ program

Teaching Tips

Introduction

1. Define the terms computer program and programming.

2. Use the recipe analogy to give students an idea of the process of programming.

C++ Programming: From Problem Analysis to Program Design, Eighth Edition 2-3

A Quick Look at a C++ Program

1. Note that every C++ program must have a function called main. Use Example 2-1 to

illustrate a basic main function. Walk through this example and point out the meaning

of each line.

2. Discuss the purpose of an output statement and what it produces.

3. Point out the use of comments.

4. Briefly introduce the #include directive.

5. Use Figure 2-1 to describe the various parts of a C++ program.

6. Use Figures 2-2 and 2-3 to describe how memory is allocated and used to store values.

The Basics of a C++ Program

2. Define the terms syntax rules and semantic rules as they relate to a programming

language and explain the difference between the two.

Teaching

Tip

Emphasize that compilers check for syntax but not semantic errors. Give an

example of each type of error.

Comments

2. Describe the two forms of comments shown in the textbook.

Teaching

Tip

Reassure students that although most of this example probably looks confusing,

they will soon understand it and be comfortable with it.

C++ Programming: From Problem Analysis to Program Design, Eighth Edition 2-4

Teaching

Tip

The importance of documenting a program cannot be underestimated. It is highly

important for ensuring that the next programmer to be responsible for

maintaining the code will be able to understand what the code is supposed to do.

Special Symbols

Reserved Words (Keywords)

1. Discuss the word symbols, or keywords, used in C++, using Appendix A as a guide.

Identifiers

1. Define the term identifier as a name for something, such as a variable, constant, or

3. Use Table 2-1 to review the rules of identifier naming.

Teaching

Tip

Discuss the difference between C++ conventions and rules. For example, it is a

rule that a mathematical symbol cannot be used in an identifier name. However,

it is a convention to begin an identifier with a lowercase letter.

Whitespaces

1. Explain that whitespaces (which include blanks, tabs, and newline characters) are used

to separate special symbols, reserved words, and identifiers.

C++ Programming: From Problem Analysis to Program Design, Eighth Edition 2-5

Data Types

1. Explain that C++ categorizes data into different types in order to manipulate the data in

a program correctly. Although it may seem cumbersome at first to be so type-conscious,

emphasize that C++ has these built-in checks to guard against errors.

Teaching

Tip

Explain that C++ is called a strongly typed language because it checks for

operations between inconsistent data types. This results in more robust and error-

free programs. Demonstrate how C++ checks for data types with a simple

program that attempts to add a string and a numeric value.

2. Define the term data type as a set of values together with a set of operations.

3. Mention that C++ data types fall into three categories: simple data types, structured data

types, and pointers. Only the first type is discussed in this chapter.

Simple Data Types

1. Describe the three categories of simple data types in C++: integral, floating-point, and

enumeration.

4. Explain the purpose of the bool data type.

5. Discuss the char data type, including its primary uses. Mention commonly used ASCII

6. Use Table 2-2 to summarize the three simple data types. Point out the difference in the

amount of memory storage required, but inform students that this is system-dependent.

Floating-Point Data Types

1. Use Table 2-3 to explain how C++ represents real, or floating-point, numbers. Mention

2. Define the terms precision, single precision, and double precision.

C++ Programming: From Problem Analysis to Program Design, Eighth Edition 2-6

Teaching

Tip

Demonstrate how to find the values of float and double on a particular

system by running the program with the header file <cfloat> in Appendix F.

Encourage students to try running this program on their own computers and

comparing the results.

Quick Quiz 1

1. What is an enumeration type?

2. The maximum number of significant digits in a number is called the

____________________.

3. The data type ____________________ has only two values: true and false.

4. The ____________________ data type, the smallest integral data type, is used to

represent characters.

Answer: char

Data Types and Variables, and Assignment Statements

2. Explain the concept and syntax of an assignment.

Arithmetic Operators, Operator Precedence, and Expressions

1. Discuss the five arithmetic operators in C++ that are used to manipulate integral and

2. Define the terms unary and binary operators, and discuss the difference between them.

Order of Precedence

C++ Programming: From Problem Analysis to Program Design, Eighth Edition 2-7

Expressions

1. This section discusses integral and floating-point expressions in detail.

2. Describe the three types of arithmetic expressions in C++.

Mixed Expressions

1. Discuss the two rules for evaluating mixed expressions and illustrate these rules in

practice using Example 2-8.

Quick Quiz 2

1. A(n) ____________________ operator has only one operand.

2. You can use ____________________ to override the order of precedence rules.

3. Describe the associativity of arithmetic operators.

4. An expression that has operands of different data types is called a(n)

Type Conversion (Casting)

1. Explain how C++ avoids the hazards that result from implicit type coercion, which

occurs when one data type is automatically changed into another data type.

2. Illustrate the form of the C++ cast operator using Example 2-9.

Teaching

Tip

Students may feel a bit overwhelmed after the discussion of the static_cast

operator. Ask them to run the program from Example 2.9. They should

experiment with removing the static_cast operator from various statements,

as well as changing the variable values. Ask them to report on any unpredictable

results.

C++ Programming: From Problem Analysis to Program Design, Eighth Edition 2-8

string Type

1. Introduce the C++ data type string, which is a programmer-defined data type

available in the C++ library. Define a string as a sequence of zero or more characters.

Teaching

Tip

Emphasize that the first position of a character in a string is 0, not 1. This will be

helpful when manipulating both strings and arrays later on the text.

Variables, Assignment Statements, and Input Statements

1. Explain that data for a C++ program must be input into main memory. Mention the two-

step process to store data in the computer’s memory.

Allocating Memory with Constants and Variables

1. Emphasize that when allocating memory, the programmer must instruct the computer

2. Define the term named constant and describe the syntax for declaring a named constant.

4. Give a formal definition of a simple data type.

Putting Data into Variables

Assignment Statement

1. Discuss the C++ assignment statement, including its syntax, variable initialization, and

the associativity rules of the assignment operator.

3. Use Example 2-14 to discuss the importance of doing a walk-through (tracing values

through a sequence of steps) when writing code.

Teaching

Tip

Building a table showing the values of variables at each step of the program is

very helpful for students to understand the nature of variables.

Saving and Using the Value of an Expression

1. Explain the steps involved in saving the value of an expression using Example 2-15.

Declaring and Initializing Variables

2. Emphasize that it is a good practice to initialize variables while they are being declared.

Use one or more examples to illustrate how to do this in C++.

Input (Read) Statement

1. This section teaches your students to read data into variables from a standard input

Variable Initialization

1. Reiterate that a variable can be initialized either through an assignment statement or a

read statement. Explain why the read statement option is more versatile. Use Example

2-19 to illustrate both types of initialization.

Teaching

Tip

Programmers (and instructors) have various approaches or preferences regarding

variable declaration and initialization. Share your views on the topic. Do you

think the best approach is to always initialize variables for consistency? Do you

prefer initializing variables directly before the block of code that uses them, or

initializing them during declaration?

Quick Quiz 3

1. What is a named constant?

C++ Programming: From Problem Analysis to Program Design, Eighth Edition 2-10

Answer: A memory location whose content is not allowed to change during program

execution

2. What is the syntax for declaring single or multiple variables?

3. True or False: If you refer to an identifier without declaring it, the compiler will

generate an error message.

4. A variable is said to be ____________________ the first time a value is placed in it.

Increment and Decrement Operators

1. Explain the purpose of the C++ increment (++) and decrement (—) operators.

2. Discuss how pre and post versions of these operators affect the results in a program.

Use Example 2-20 to help explain the difference between these versions.

Teaching

Tip

Verify that students are comfortable with using pre- and post-

increment/decrement operators correctly, as it will be useful when working with

control structures.

Output

1. Review how the C++ output statement is coded with the cout object and stream

insertion operator (<<). Review the role of the endl manipulator in output statements

as well.

2. Discuss the use of escape characters (see Table 2-4), such as the newline character, to

format output. Demonstrate how to format output with Examples 2-21 through 2-26.

Teaching

Tip

Outputting strings can be confusing at first. Talk about the various methods to

deal with several lines of string output, and give your opinion as to the best

approach. Emphasize that the Enter key cannot be used to break up a long string

into two lines.

C++ Programming: From Problem Analysis to Program Design, Eighth Edition 2-11

Preprocessor Directives

1. Explain the role of the preprocessor in C++. Discuss the use of header files and the

syntax for including them in a C++ program.

Teaching

Tip

Show your students some of the available operations in the <cmath> header.

Here is one Web site with a description:

http://www.cplusplus.com/reference/cmath/

namespace and Using cin and cout in a Program

1. Briefly explain the purpose of the namespace mechanism in ANSI/ISO Standard

2. Review the using namespace std; statement and its usefulness in programs

using cin and cout statements.

Using the string Data Type in a Program

Creating a C++ Program

1. Discuss the role of the function main in a C++ program. Go over the syntax of a main

function, including declaration, assignment, executable, and return statements. Mention

that named constant definitions and preprocessor directives are written before the main

function.

2. Spend some time stepping through Examples 2-27 through 2-29. Verify that students

Debugging: Understanding and Fixing Syntax Errors

1. Review the sample program on page 84 and the compiler output that is generated when

compiling the program. Walk through the various syntax errors and explain how each

one should be fixed. Note that a syntax error on one line may be the cause of a compiler

error on the following line.

C++ Programming: From Problem Analysis to Program Design, Eighth Edition 2-12

Teaching

Tip

Debugging is one of the most important skills a professional programmer

acquires. Stress to students the importance of learning how to debug their own

programs, including the verification of the results.

Program Style and Form

1. This section covers basic C++ syntax and semantic rules. Review these rules with your

students in order for them to feel comfortable writing a complete functioning C++

program.

Syntax

1. Remind students that syntax rules define what is legal and what is not.

2. Discuss some common syntax errors. Emphasize that syntax errors should be corrected

Use of Blanks

1. Discuss when blanks should and should not be used in a C++ program.

Use of Semicolons, Brackets, and Commas

1. Explain the purpose and meaning of semicolons, brackets, and commas in C++

programs. Define the term statement terminator.

Semantics

1. Define the term semantics.

2. Reiterate that a program may run without compiler errors and still have semantic errors

that generate incorrect results. Use the example in the text to illustrate.

Naming Identifiers

1. Mention the conventions for naming identifiers, including self-documenting identifiers

and run-together words.

Prompt Lines

2. Explain why well-written prompt lines are essential for user input.

Documentation

1. Discuss why documenting a program through comments is critical to understanding and

Form and Style

1. Explain the purpose behind formatting and indentation conventions in source code. Use

Example 2-30 to illustrate.

Teaching

Tip

As with naming conventions, discuss your own preferences in terms of form and

style in programming. Use the programming examples at the end of the chapter

to talk about various stylistic elements. Discuss the value of the “art” of

programming.

Quick Quiz 4

1. True or False: The semantic rules of a language tell you what is legal and what is not

legal.

2. The semicolon is also called the ____________________.

3. How can you make run-together words easier to understand?

4. Why are comments important in a program?