// FILE: 98ab3.cpp 
// PURPOSE: Test implementation of solutions to 1998 AB Exam: Question 3 
//---------------------------------------------------------------------
// COMPILATION INSTRUCTIONS: g++ and gxx 
// 1. FILES: All the files must be in directory in which you compile
// 2. COMMAND LINE: g++ (or gxx) 98ab3.cpp 
//--------------------------------------------------------------------
#include <iomanip.h>
#include <string>


struct ListNode {
  int         info;
  ListNode *  next;
  ListNode(int val, ListNode * ptr)   // constructor
    : info(val), next(ptr) { }
};

ListNode * FirstMin(ListNode * list)  {
  // postcondition: returns pointer to node with minimal value in list
  //                returns pointer to first such node if more than
  //                one node contains the minimal value    

  return list;
}

void RemoveNext(ListNode * ptr) {
  // precondition: ptr != NULL   


}

void RemoveDupMins(ListNode * list) {
  // postcondition: all but first minimal nodes removed from list    


}


void testFirstMin(void);
void testRemoveNext(void);
void testRemoveDupMins(void);
void testRemoveNext(void);
void initList(ListNode *&, int); 
void Print(ListNode *, const string &);
void pause(void);
void cls(void);


int main() {
    string title("1998 AB Exam: Question 3");
    cls(); 
    cout << setw(39 + title.length()/2) << title.c_str() << "\n\n";
        
    testFirstMin();
    testRemoveNext();
    pause();
    cls();    
    testRemoveDupMins();    
    pause();
    return 0;
}

/////////////////////////////////////////////


void testFirstMin(void) {
    ListNode *L1, *L2,*L4;
    initList(L1, 1); initList(L2, 2); 
    initList(L4, 4); L4->next = NULL;
    cout << "Testing FirstMin:\n\n";
    Print(L1, "L1");
    ListNode *p = FirstMin(L1);
    cout << "After p = FirstMin(L1): p->info = " 
         << p->info << "\n\n";        
    Print(L2, "L2");
    p = FirstMin(L2);
    cout << "After p = FirstMin(L2): p->info = " 
         << p->info << "\n\n";
    Print(L4, "L3");
    p = FirstMin(L4);
    cout << "After p = FirstMin(L3): p->info = " 
         << p->info << endl;
}


void testRemoveNext(void) {
  ListNode * L1 = new ListNode(10, new ListNode(5,new ListNode(20,NULL)));
  ListNode * L2 = new ListNode(10, new ListNode(5,new ListNode(20,NULL)));  
  cout << string(60, '*') << endl;     
  cout << "Testing RemoveNext:\n\n";
  ListNode *ptr = L1;
  cout << "ptr->info = " << ptr->info << " and "; Print(L1, "L1");
  RemoveNext(ptr);
  cout << "After RemoveNext(ptr): "; Print(L1, "L1");
  ptr = L2->next->next;
  cout << "\nptr->info = " << ptr->info << " and "; Print(L2, "L2");
  RemoveNext(ptr);
  cout << "After RemoveNext(ptr): "; Print(L2, "L2");  
  ptr = L2->next;
  cout << "\nptr->info = " << ptr->info << " and ";  Print(L2, "L3");
  RemoveNext(ptr);
  cout << "After RemoveNext(ptr): "; Print(L2, "L3");      
}

void testRemoveDupMins(void) {
   ListNode *L1, *L2, *L3, *L4;
   initList(L1, 1); initList(L2, 2); initList(L3, 3); initList(L4, 4); 
   cout << "Testing RemoveDupMins:\n\n";
   Print(L1, "L1"); RemoveDupMins(L1);
   cout << "After RemoveDupMins(L1): "; Print(L1, "L1");
   Print(L2, "\nL2"); RemoveDupMins(L2);
   cout << "After RemoveDupMins(L2): "; Print(L2, "L2");   
   Print(L3, "\nL3"); RemoveDupMins(L3);
   cout << "After RemoveDupMins(L3): "; Print(L3, "L3");   
   Print(L4, "\nL4"); RemoveDupMins(L4);
   cout << "After RemoveDupMins(L4): "; Print(L4, "L4");           
}


void initList(ListNode *&L, int n) {
   ListNode * list1 = new ListNode(3, new ListNode(0,
                      new ListNode(12, new ListNode(0,NULL))));    
   ListNode * list2 = new ListNode(5, new ListNode(4,
                      new ListNode(5, new ListNode(2,NULL))));
   ListNode * list3 = new ListNode(10, new ListNode(10,
                      new ListNode(10, new ListNode(20, new ListNode(10,NULL)))));
   ListNode * list4 = new ListNode(10, new ListNode(10,NULL));
   ListNode * A[] = {list1, list2, list3, list4};
   L = A[n-1];
}

void Print(ListNode * list, const string &Lst) {
   cout << Lst << "-->";
    while (list != NULL) {
       cout << "[" << list->info << "]-->";
       list = list->next; 
    }
    cout << "NULL" << endl;
}

void pause(void) {
  cout << "\nPress <ENTER>...";
  cin.ignore(80, '\n');
}

void cls(void) {
  for (int k = 1; k <= 55; k++)
    cout << '\n';
}