1. Chapter 13 Introduction to C++ Language
By C. Shing
ITEC Dept
Radford University

2. Objectives
Understand C++ features
Understand Program Structure in C++

3. C++ Features Type language (stronger type than C)
Variable must be declared a type
(declaration mixed with statements)
has boolean data type bool (false, true)
Class: hide member data (only member function can access them),
provide public interface by member function
Overloading (operator and function):
same function/operator name with different
argument list
Inheritance and Polymorphism: virtual function
Template
Same function task for different data types

4. Running C++ Program C source program -> C++ Compiler
-> Object program -> Link
->(feed data) Excution

5. Program Structures File Extension
.cc (or .cpp)
Compile & link (Solaris) , then execute
g++ mainfile.cc [sub1filename.cc sub2filename.cc]
then
a.out or
g++ -o executable mainfile.cc
[sub1filename.cc sub2filename.cc]
executable

6. Program Structures (Cont.)
Compile only (Solaris)
g++ –c filename.cc

7. Program Structures (Cont.)
mainfile.cc /*
**********************************
* This is a comment *
* Block * */
// Comment line
// Declaration for standard library
// The following line is required
#include <iostream>

8. Program Structures (Cont.)
// all C library declaration starts with c
#include <cmath> //if math library is used
// The following file yourdeclaration.h
// is in your current directory
//#include “yourdeclaration.h”
using namespace std; // for cin and cout
// declare named global constants
const int number = 4;
const double PI = ;
const char MY_MESSAGE[] = “Good Morning!”;

9. Program Structures (Cont.)
// declare types
typedef char myCharacter;
// declare global variables
int a;
char b=‘a’, c=‘\n’;
myCharacter e;
long d = 14000L; // this means long int (default int)
float x=-2.5F;
double y=2.5;

10. Program Structures (Cont.)
// declare function prototype
int sub1(int);
// define main function
int main () {
int lc = 2;
// call function
int lb = sub1(lc);
cout << lb <<endl;
return 0; // no error exit }

11. Program Structures (Cont.)
// define function
int sub1 (int l) {
// call function
int la = 5*l;
return la; }

12. Variable Variable declaration Pointer variable declaration
Form: type variable [=initial value];
e.g. int number;
Pointer variable declaration
Form: type *variable [=initial value];
e.g. int* numberptr=0;
// numberptr is initialized to null pointer

13. Constant Variable Constant variable declaration
Form: const type variable;
e.g. const double PI = ;
Constant address (or pointer variable)
declaration
Form: pointer type const variable;
e.g. double * const PIptr;

14. Variable (Cont.) Constant address points to constant variable
declaration
Form: const pointer type const variable;
e.g. const double * const PIptr;
Alias or reference variable
(must initialize when declare it)
Form: type &alias=variable;
e.g. int number=10;
int &numberalias=number

15. Difference Between Alias and Pointer
Alias must have variable value (not null).
Pointer can be null.
Alias will not be reassigned once declared,
only the value will be changed
Alias can access the variable directly,
pointer accesses the variable indirectly

16. Difference Between Alias and Pointer (Cont.)
Example:
ref.cc

17. Assignment Statement Casting:
Identifier = static_cast<left hand side type> (expression)
Example: int number = static_cast<int>(3.1416);
Then number contains 3

18. Loop Statement – for (Cont.)
Example:
// loop index can be defined inside for loop
// and only meaningful within the loop
for (int i=0;i<=5;++i) {
cout << “TRUE is printed!\n”; // print 5 times }

19. Format Data Stream Need #include <iomanip> format.cc
setw(): set total # of spaces to print
if not enough, give exact # of spaces needed
setiosflags(ios::fixed|ios::showpoint):
print decimal point
setprecision():
set total # of spaces after decimal point
format.cc

20. Example without Using Class
hello.cc
hello1.cc
hello2.cc

21. Program Structures (Using Class)
Problem: Write a class Dice to simulate
flipping two dices.
Example 2

22. Program Structures (Using Class)- Cont.
Problem: Write a class Dice to simulate
flipping two dices. (Cont.)
Use Modules:
driver
class implementation
class specification
header file

23. Compare C++ to Java Program
Problem: Write a class Dice to simulate
flipping two dices.
Example 3
dice.java

24. Reference: Deitel & Deitel: C How to Program, 4th ed.,
Chapter 15, Prentice Hall