// Recursive factorial function
#include <iostream.h>
#include <iomanip.h>

unsigned long factorial(unsigned long);

main()
{
   for (int i = 0; i <= 10; i++)
      cout << setw(2) << i << "! = " << factorial(i) << endl;

   return 0;
}

// Recursive definition of function factorial
unsigned long factorial(unsigned long number)
{
   if (number <= 1)
      return 1;
   else
      return number * factorial(number - 1);
}