Continuing on Linked Lists(Finding and Deleting Specified Links)

Finding and Deleting Specified Links:

Search a linked list for a data item with a specified key value and to delete an item with a specified key value.These along with insertion at the start of the list are the same operations carried out by the Link List workshop.follow the below sample code.

Work Shop with Code:

/**
 * @author Abhinaw.Tripathi
 *
 */

class Link
{
  public int idata;
  public double dData;
  public Link next;

  public Link(int id,double dd)
  {
 this.idata=id;
 this.dData=dd;
  }

  public void displayLink()
  {
 System.out.println(" {  " +idata + "," +dData + "} ");
  }
}

class LinkList
{
  private Link first;
  public LinkList()
  {
first=null;
  }

  public void insertFirst(int id,double dd)
  {
 Link newLink=new Link(id, dd);
 newLink.next=first;
 first=newLink;
  }

  public Link find(int key)
  {
 Link current=first;
 while(current.idata!=key)
 {
 if(current.next == null)
 return null;
 else
 current=current.next;
 }
 return current;
  }

  public Link delete(int key)
  {
 Link current=first;
 Link previous=first;
 while(current.idata!=key)
 {
 if(current.next==null)
 return null;
 else
 {
 previous=current;
 current=current.next;
 }
 }

 if(current == first)
 first=first.next;
 else
 previous.next=current.next;
 return current;
  }

  public void displayList()
  {
 System.out.println("First----->Last : ");
 Link current=first;
 while(current!=null)
 {
 current.displayLink();
 current=current.next;
 }
 System.out.println(" ");
  }

}

public class LinkListApp {

/**
*
*/
public LinkListApp() {
// TODO Auto-generated constructor stub
}

/**
* @param args
*/
public static void main(String[] args) {
// TODO Auto-generated method stub


LinkList theList=new LinkList();
theList.insertFirst(22, 2.99);
theList.insertFirst(44, 8.99);
theList.insertFirst(66, 4.99);
theList.insertFirst(88, 6.99);

theList.displayList();

Link f=theList.find(44);
if(f!=null)
System.out.println("Found link with key " + f.idata);
else
System.out.println("Can't find the link");

Link d=theList.delete(66);
if(d!=null)
System.out.println("Deletd link with the key " +d.idata);
else
System.out.println("Cant delete link");

theList.displayList();
}



}

The desire output will be like this

First----->Last :
 {  88,6.99}
 {  66,4.99}
 {  44,8.99}
 {  22,2.99}

Found link with key 44

Deletd link with the key 66

First----->Last :
 {  88,6.99}
 {  44,8.99}
 {  22,2.99}