A recursive function to calculate the factorial of a given positive number:
void main()
{
int n,c;
clrscr();
printf("enter the number :");
scanf("%d",&n);
c=fact(n);
printf("factorial of %d = %d",n,c);
getch();
}
fact(int n)
{
int factorial;
if(n==1||n==0)
return(1);
else
factorial=n*fact(n-1);
return (factorial);
}