Introduction of C

Inroduction

c is a procedural programming language.it was developed by Dennis Ritchie between 1963 and 

1973.

It was mainly developed as a system programming language to write operating system.

The feature of C language:

      Low-access to memory.

      Simple Set of keyword.

      clean style

The C program is the human-readable form, while the executable that comes out of the compiler is the machine-readable and executable form.

Structure Of C program:

    1.Header File

    2.Main()

    3.Variable Declaration

    4.Body

    5.Return

1]Header File:

The first and foremost component is the inclusion of the Header files in a C program.

A header file is a file with extension .h which contains C function declarations and macro definitions.

Following are some header files of c language.

    stddef.h = Defines different types of declartion and macro.

    stdiint.h = Define exact width of integer value.

    stdio.h = Defines input and output functions.

    stdlib.h = Defines numeric conersion to any other datatype.

    string.h = Defines the string functions.

    math.h = Defines the math functions.

       Syntax of the header file:

      #include<(header_file_name).h>

2] Main Method Declaration:

 After the declaration of headerfile main() function shoud be declared.

 Syntax Of the Main function:

   

  void main()

{

 }

3] Variable Declaration:

 In c program you shoud not use any variables without declared them.

 The variables are declared before any of the function operation.

  Syntax Of the variable Declaration:

int a;

 

where int is a datatype and [a] is name of variable.

 Note: Variables are always declared with any of the data type. The datatypes are also available in c which we are discussed letter.

4]Body : 

This part is defines the operation performd on the function. The operation can be anything like addition,searching,printing,sorting,etc.

     Syntax:

void main()

         {

        int a;

printf("%d",a);

}

5]Return Statement:

The return statement refers to the returning of the values from a function. This return statement and return value depend upon the return-type of the function.

For example, if the return type is void, then there will be no return statement. In any other case, there will be a return statement and the return value will be of the type of the specified return-type.