//		person.hh

 const int YOUNGER=-1, EQUAL_AGE=0, OLDER=1;

 const int LNAME = 50;		// max. Laenge eines Namens
 struct Datum			// Datensatz fuer das Datum
   {
     int tag, monat, jahr;
   };

 struct Person			// Datensatz fuer eine Person
   {
     char name[LNAME];
     Datum geburtstag;
     float gehalt;
   };

/**	Reads the data for a variable of structure Person
	@param	t	data to read
*/
void Read(Person& t);

/**	Prints the data for a variable of structure Person
	@param	t	data to print
*/
void Print(const Person& t);

/**	Compares the age of two persons.
	@param	a	first person
	@param	b	second person
	@return		{-1, 0, 1} means person a is {younger, equal aged, older} wrt. person b
*/
int AgeComp(const Person& a, const Person& b);


/**	Sets an index vector idx such that Person a[idx[i-1]] is
	younger than or equal aged as a[idx[i]].
	@param	n	#persons in array
	@param	a	array of persons
	@param idx	index array
*/
void Sort(const int n, const Person a[], int idx[]);


/**	Sets an index vector idx such that Person a[idx[i-1]] is
	younger than or equal aged as a[idx[i]].
	(C) Clemens Pechstein
	@param	n	#persons in array
	@param	a	array of persons
	@param idx	index array
*/
void MinSort(const int n, const Person a[], int idx[]);