Tuesday, 2 August 2011

RECURSIVE FUNCTIONS



we can develop the functions in two ways
1. iterative method
2. recursive method

Iterative functions – are loop based imperative repetitions of a process (in contrast to recursion which has a more declarative approach).

Q: Is the recursive version usually faster?
A: No -- it's usually slower (due to the overhead of maintaining the stack)

Q: Does the recursive version usually use less memory?
A: No -- it usually uses more memory (for the stack).

Q: Then why use recursion??
A: Sometimes it is much simpler to write the recursive version (but we'll need to wait until we've discussed trees to see really good examples...)

The recursive version is

* a little shorter,
* a little clearer (closer to the mathematical definition),
* a little slower

#include<stdio.h>
#include<conio.h>
int fact(int n)
{
 if(n==0)
  return 1;
 else
  return(n*fact(n-1));
}
void main()
{
 int n;
 clrscr();
 printf("enter n value\n");
 scanf("%d",&n);
 printf("factorial function is%d\n",fact(n));
 getch();
}


Functions

No comments:

Post a Comment