Give the structure of 'C' programming. Also, give significance of math.h and string.h header files.

General form of c program is...

Global declarations
int main(parameter list)
{
statement sequence
}
return-type f1(parameter list)
{
statement sequence
}
return-type f2(parameter list)
{
statement sequence
}...
return-type fN(parameter list)
{
statement sequence
}

This form is mainly concerned with Functions and Declarations.

Significance of math.h file

math.h header files drives hundreds of maths functions along with one macro. This header file returns result as double and takes double as an argument.

Significance of string.h file

string.h header file drives string related functions . This header file defines any one variable type, one macro, and number of functions.

Basically header file contains Declarations, Definitions, and Macro of related number of functions which is defined in that particular header file.

Thanks

Regards

Mahesh v Kondawar

Hello Ishwari
We know we have already defined data types like int, char, float, double.
Let's take int
When we declare
int i ;
It simply means an area of 2 Bytes(architecture dependent) gets allocated and the area is named as i and as our houses get some address in a street, in the same manner, this area will also have an address.

Now if we want some area which must contain say some 5 Bytes and that area has to be divided into 3 areas.
we want to give the first division to an int , the 2nd division to a char, the 3rd division to another int.
So this type of data type is not already defined.

So we need to make a data type like this on our own.

How to do that?
We use structure.

struct datatype
{
    int i;
    char c;
    int j;
};

Now if we declare
datatype x;
Then x will have our desired memory allocation.


Math.h 
has function definitions of the mathematical functions that we use.
example : pow()

Similarly, string.h has functions that we use t manipulate strings. 
 

#include<stdio.h> //header file

main() // entry point for a program

{

// variables declaration

//logic which you want to achieve

}

math.h is a header file for working with mathmatical functions like abs() sum() etc..

string.h is also header file for working with string functions like strupr(),strlwr() etc.. 

without writing any manual code you can use these functions in your program for your purpose

ex: strlwr("nani") is automatically converted to "NANI" which is the output

The basic structure of a C program is : 

Preprocessor directives to include libraries required for execution of the program

Declaration of global variables and macros

main() function{

                 code   ;

}

other function definitions

1. math.h is a header file that is to be include in the program if functions like sqrt(), pow(), abs() sin() etc. are to be called.

2. string.h is a header file that includes various funcitons for working on strings. These include strlen(), strcmp(), strcat(), etc.

Hi Ishwari, I am glad to see students like you who are keen to learn to programme. As we all know that c is an excellent programming language which made a platform for various other software and operating systems. To make it such a secure language header file were made, which includes several functions. The header file like math.h is responsible for doing several mathematical calculations like power calc, sqrt calc and several trigonometrical calc and string.h is accountable for doing wonders like string copy, concatenation, changing upper case letters to lower case and vice versa with strings(a combination of characters).

The syntax for including math.h and string.h is:-

#include<math.h>

#include<string.h>

Thank you. I hope this will help you. Good luck.