User define function,c++ please...?

please show example n explanation...thanks...

User define function,c++ please...?
a function basically has two parts to it





%26lt;return type%26gt; function_name(%26lt;parameter types)


{





//code goes here


// code goes here


// this function must return a value if has a datatyp other than void


}





take for example the main function:





#include %26lt;iostream%26gt;





void main()


{


using namespace std;





}





this main function doesn't have a return datatype nor does it have datatype in parameters





now let's create a function that calculates the exponent of a number:





int exponent(int base, int power)


{





int result = base;





for(int i=0; i %26lt; power; i++)


result *= base;





return result;


}





this function takes in two values, the base of the number and the power of the number, then it returns a result after the algorithm.





i hope this helps, the easiest way to understand this is through practice. lots of it.
Reply:hi,


Many functions are already available to use. Those functions are available in header files (.h) those are included in ur programe through the statement


#include%26lt;some header file name%26gt; e.g.,


#include%26lt;stdio.h%26gt; or #include%26lt;conio.h%26gt;





But still u have to define ur own functions for specific needs of ur programme. These functions perform the functions these are designed for. e.g. to add two integers u write a function as follows:





int add(int , int ); //this is prototype of the function. It tells this function will take 2 integers with it and will bring the sum of these 2 integers.





int add(int x, int y)


{


return x+y;


}





In other words, this add(int x,int y) may not be available in any of the header files, so u have to design ur own function.