CSC 3 S2

• <iostream> : Contains function prototypes for the C++ standard input and standard output functions. This header file replaces header file <iostream.h>
• <iomanip> : Contains function prototypes for stream manipulators that format streams of data. This header file replaces header file <iomanip.h>
• <cmath> : Contains function prototypes for math library functions. This header file replaces header file <math.h>
• <cstdlib> : Contains function prototypes for conversions of numbers to text, text to numbers, memory allocation, random numbers and various other utility functions. This header file replaces header file <stdlib.h>.
• <ctime> : Contains function prototypes and types for manipulating the time and date. This header file replaces header file <time.h>
• Important Component/Features of C++ Language

  1. Comment
  2. Header file & preprocessor directive
  3. Function
  4. Body
• Comment:

  //Author-ICT Lecturer /* My first program in C++ and there will be more programs after this"/
• Header file : #include <iostream> using namespace std;
• Function :

  int main ()

  {
• Body: cout <<"Hello World!";

  cout <<"\n";

  system ("PAUSE");

  return 0;

  }
• The purpose to insert a comment: 1. To document a program

  2. To improve the program readability
• Line comment : discards everything from where the pair of slash signs (//) are found up to the end of that same line @ normally used for single line comment
• Block comment discards everything between the /* and the first appearance of the */ with the possibility of including multiple lines @ possibly containing many lines
• Header file is a text file containing small bits of program code, which is used to describe the contents of the main body of code to other modules
• Header file:

  1. <iostream>
  2. <cmath>
• Preprocessor directive

  1. #include
• #include <iostream> : declare objects that control reading from and writing to the standard streams
• #include <iostream> : cin, cout, DLL

  cin : console input

  cout : console output
• #include<cmath> : Mathematical declarations to perform calculations
• #include<cmath> : pow, sqrt

  pow : Raise to power

  sqrt : Return the square root of x
• Example

  cout<<"The square root of the radius is: "<<sqrt(radius)<<endl;

  cout<<"The area of the circle is: "<<3.1416 pow(radius, 2)<<endl;
• Function: a group of code statements which are given a name
• BODY The body may consists of: 1. Reserved word 2. Variable declaration 3. Input/Output console 4. C++ statement 5. Return statement