// FILE: 1ab3.cpp 
// PURPOSE: Linked list problem practice
//---------------------------------------------------------------
// COMPILATION INSTRUCTIONS: g++ and gxx 
// COMMAND LINE: 
//    g++ (or gxx) 1ab3.cpp 
//----------------------------------------------------------------
// PROGRAMMING INSTRUCTIONS:
// Read question  below and complete AddStudent() accordingly
//----------------------------------------------------------------
#include <iomanip.h>
#include <stdlib.h>
#include <string>
/*--------------------------------------------------------------
This question involves the two structures declared below. The first
one is used to store information about one student; the second one
is used to implement linked lists of students.

struct Student {
   Student(const string &="", int=0);
   string name;
   int age;
};

struct ListNode {
   Student data;
   ListNode *next;
};

Write function AddStudent as started below. Function AddStudent should
add a new person to the given list, which is sorted in ascending order
according to the ages of the students in the list. In particular,
function AddStudent should create a list node whose data field is a
student with the given name and age and should insert the new node
into the linked list pointed to by L at the appropriate place. (If
there is already a student with the given age, the new node can be
inserted either before or after that node.)

EXAMPLE 1:

Value of L and its list        Function call
-----------------------        ------------------------
L--> NULL                      AddStudent(L, "Jean", 16)


Resulting value of L and its list
---------------------------------
     ___________.
     |name: Jean|
L--> |age:  16  |--> NULL
     +----------+

EXAMPLE 2:

Value of L and its list                      Function call
---------------------------------            --------------------
     ___________.    ___________.            AddStudent(L, "Yve", 3)
     |name: Pat |    |name: Jean|
L--> |age:  14  |--> |age:  16  |--> NULL
     +----------+    +----------+


Resulting value of L and its list
---------------------------------
     ___________.    ___________.    ___________.
     |name: Yve |    |name: Pat |    |name: Jean|
L--> |age:  3   |--> |age:  14  |--> |age:  16  |--> NULL
     +----------+    +----------+    +----------+

Complete function AddStudent below. Assume that it is only called
with values that satisfy its precondition.

void AddStudent(ListNode *&L, const string &name, int age) {
// pre: L is NULL or it points to the first node of a linked list;
//  the list is sorted according to the ages of the students in the list
--------------------------------------------------------------*/

struct Student {
  Student(const string &nm="", int ag=0) :
    name(nm), age(ag) {} 
  string name;
  int age;
};

struct ListNode {
   Student data;
   ListNode *next;
};

void AddStudent(ListNode *&L, const string &name, int age) {

} //*** AddStudent


void print(ListNode *L, bool, Student);
void driver1(ListNode *&);
void driver2(ListNode *&);


int main(void) {
  ListNode *P = NULL;
  driver1(P);
  driver2(P);

  return 0;
}

void print(ListNode *L, bool beforeAddStudent, Student std) {
  cout << "\n" << ( beforeAddStudent ? "BEFORE " : "AFTER " )
       << "AddStudent(L, \"" << std.name << "\", " << std.age
       << "):" << "\n\nL--> ";
  if ( L !=  NULL ) {
    for (ListNode *L2 = L;  L2 != NULL; L2 = L2->next ) {
      cout << "name: " << L2->data.name << setw(8 - L2->data.name.length()) 
	   << setiosflags(ios::left) << "-->";
    }
  }
  cout << " NULL" << endl;
  if ( L == NULL )  return;
  cout << "     ";
  for (ListNode *L2 = L;  L2 != NULL; L2 = L2->next ) {
    cout << "age:  " << setw(8) << L2->data.age;
  } 
  cout << endl << endl;
}//*** print


void driver1(ListNode *&L) {
  string title("Linked List Problem: EXAMPLE 1");
  cout << "\n\n\n\n\n\n" << setw(39 + title.length()/2) << title.c_str() << endl;
  print(L, true, Student("Jean", 16));
  AddStudent(L, "Jean", 16);
  print(L, false, Student("Jean", 16));
  cout << "\n\nPress <ENTER>: "; cin.ignore(10, '\n');
}//*** driver1



void driver2(ListNode *&L) {
  string title("Linked List Problem: EXAMPLE 2");
  cout << "\n\n\n\n\n\n" << setw(39 + title.length()/2) 
       << title.c_str() << endl;
  ListNode *L2 = new ListNode; 
  L = L2; L2->data = Student("Pat", 14);
  L2->next = new ListNode;  L2 = L2->next; 
  L2->data = Student("Jean", 16);  L2->next = NULL;
  print(L, true, Student("Yve", 3));
  AddStudent(L, "Yve", 3);
  print(L, false, Student("Yve", 3));
  cout << "\n\nPress <ENTER>: "; cin.ignore(10, '\n');
}//*** driver2