Thread: factorial

Are you looking for a way to calcuate a factorial? If so, here's a recursive one.

Code:

#include <stdlib.h>
#include <stdio.h>

int factorial(int n);
int main(void)
{
   int n;

   printf("Enter number for which to calculate factorial:");
   scanf("%d",&n);
   printf("%d! = %d\n",n,factorial(n));
   return 0;
}

int factorial(int n)
{
   if (n == 0)
      return 1;
   else
      return n*factorial(n-1);
}

It´s not the optimal solution to solve this simple problem recoursively.
The recoursion wastes a high amount of your stack memory.

better:

Code:

unsigned int factorial(int n);
{
  unsigned int fact=1;

  for(;n>1;fact*=n, n--) ;

  return fact;
}

klausi