giao trinh tin hoc 9385

Chapter 1 – Introduction to C++
Programming
Outline
1. History of C and C++
2. C++ Standard Library
3. Basics of a Typical C++ Environment
4. Introduction to C++ Programming
5. A Simple Program: Printing a Line of Text
6. Another Simple Program: Adding Two Integers
7. Arithmetic
8. Decision Making: Equality and Relational Operators
9. Introduction to Object Technology

 2003 Prentice Hall, Inc. All rights reserved.

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History of C and C++
• History of C
– Evolved from two other programming languages
• BCPL and B
– “Typeless” languages

– Dennis Ritchie (Bell Laboratories)
• Added data typing, other features

– Development language of UNIX

– Hardware independent
• Portable programs

– 1989: ANSI standard
– 1990: ANSI and ISO standard published
• ANSI/ISO 9899: 1990

 2003 Prentice Hall, Inc. All rights reserved.


3

History of C and C++
• History of C++
–
–
–
–

Extension of C
Early 1980s: Bjarne Stroustrup (Bell Laboratories)
“Spruces up” C
Provides capabilities for object-oriented programming
• Objects: reusable software components
– Model items in real world
• Object-oriented programs
– Easy to understand, correct and modify

– Hybrid language
• C-like style

• Object-oriented style
• Both
 2003 Prentice Hall, Inc. All rights reserved.


4

C++ Standard Library
• C++ programs
– Built from pieces called classes and functions

• C++ standard library
– Rich collections of existing classes and functions

• “Building block approach” to creating programs
– “Software reuse”

 2003 Prentice Hall, Inc. All rights reserved.


String Manipulation Functions of the Stringhandling Library
• Determining string lengths
– size_t strlen( const char *s )
• Returns number of characters in string
– Terminating null character not included in length

 2003 Prentice Hall, Inc. All rights reserved.

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// Using strlen.
#include <iostream>
using std::cout;
using std::endl;
#include <cstring> // prototype for strlen
int main() {
char *string1 = "abcdefghijklmnopqrstuvwxyz";
char *string2 = "four";
char *string3 = "Boston";

cout << "The length of \"" << string1
<< "\" is " << strlen( string1 )
<< "\nThe length of \"" << string2
<< "\" is " << strlen( string2 )
<< "\nThe length of \"" << string3
<< "\" is " << strlen( string3 ) << endl;
return 0; // indicates successful termination
} // end main

The length of "abcdefghijklmnopqrstuvwxyz" is 26
The length of "four" is 4
The length of "Boston" is 6

 2003 Prentice Hall, Inc.
All rights reserved.