/****************************************************
*  Purpose:
*          Demonstrate the use of basic operations
*          on a singly linked list.
*
********************************************************/

#include <iostream.h>
#include "llist.h"

using namespace std;

void PrintList(Node_Ptr Head);


/*****************  Main Function Starts Here ***********/
int main() {

Node_Ptr	Head;
Node_Ptr	NewNode_Ptr;
Node_Ptr	Curr_Ptr;
Node_Ptr	Prev_Ptr;
Element_Type 	InValue;

/*------------Create a linked list--------------------------*/


cout << "Enter values for linked list, one per line." << endl
     << "Enter 999 to end list." << endl;

Head = new LinkNode;
cin >> Head->data_member;
Curr_Ptr = Head;

cin >> InValue;

while (InValue != 999)
    {
    NewNode_Ptr 		= new LinkNode;
    NewNode_Ptr->data_member 	= InValue;
    Curr_Ptr->link_member 	= NewNode_Ptr;
    Curr_Ptr 			= NewNode_Ptr;
    cin >> InValue;
    } // end while

Curr_Ptr->link_member = NULL;	// mark the tail

PrintList(Head);		// display the list

/*------------Add a node to the linked list-------------------*/

cout << "Enter a value for a new last node: ";
cin >> InValue;

/**************** ADD CODE HERE TO ADD A NODE TO THE
		END OF THE LINKED LIST  *********************/


cout << endl << "The list after the addition follows:" << endl;
PrintList(Head);		// display the list

/*------------Insert a node in linked list-------------------*/

cout << "Enter the value of node to insert in the list: ";
cin >> InValue;

NewNode_Ptr 		= new LinkNode;
NewNode_Ptr->data_member = InValue;

Prev_Ptr = NULL;
Curr_Ptr = Head;

while ( (Curr_Ptr != NULL) && (InValue > Curr_Ptr->data_member) )
    {
    Prev_Ptr = Curr_Ptr;
    Curr_Ptr = Curr_Ptr->link_member;
    }

if (Prev_Ptr == NULL)
    Head = NewNode_Ptr;
else
    Prev_Ptr->link_member = NewNode_Ptr;


NewNode_Ptr->link_member = Curr_Ptr;

cout << endl << "The list after the insertion follows:" << endl;
PrintList(Head);		// display the list



/*------------Delete a node from linked list-------------------*/

Node_Ptr	Del_Ptr;

cout << "Enter the value of a node to delete: ";
cin >> InValue;


/************ ADD CODE HERE TO DELETE A NODE ***************/


delete Del_Ptr;

cout << endl << "The list after the deletion follows:" << endl;
PrintList(Head);		// display the list

return 0;
} // end main
/***********************************************************/


/*---------------------------------------------------------
*  Function Name: PrintList
*  Parameters: 	  pointer to the head of a linked list
*  Returns:	      nothing
-----------------------------------------------------------*/

void PrintList(Node_Ptr Head) {

Node_Ptr Curr_Ptr;
Curr_Ptr = Head;	// this sets up a pointer to the Head

cout << endl << "The list contains the following values." << endl;

/**********  ADD A LOOP HERE TO PRINT OUT THE VALUES *******/


} // end PrintList