/*
Summary: Factorial is represented using '!', so five factorial will be written as (5!),n factorial as (n!).Also
n! = n*(n-1)*(n-2)*(n-3)...3.2.1 and zero factorial is defined as one i.e. 0! = 1.
*/

#include<stdio.h>
int fact(int);
int main()
{
 int num,f;

 printf("\nEnter a number: ");
 scanf("%d",&num);

 f=fact(num);

 printf("\nFactorial of %d is: %d",num,f);
 return 0;
}

//recursive function
int fact(int n)
{
 if(n==1)
  return 1;
 else
  return(n*fact(n-1));
}