# include <stdio.h>

//
//  Program 8.16, Stephen Kochan, Programming in C.
//
int main ( void );
unsigned long int factorial ( unsigned int n );

int main ( void )
{
  unsigned int j;

  for ( j = 0; j < 11; j++ )
  {
    printf ( "%2u! = %lu\n", j, factorial ( j ) );
  }

  return 0;
}

unsigned long int factorial ( unsigned int n )
{
  unsigned long int result;

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

  return result;
}