Question

JAVA: Provide two different implementations, an array and a linked list, to maintain a list of names (two separate programs).The following operations are available: insert rear, insert front, remove a particular element, and print the whole list. Do not implement an ADT(Do not use a class with data and operations) Just set up a fixed size array or a linked list of nodes in main and provide code in main or functions/static methods to perform insert, remove, and print. You can set up a menu or hard code some test cases to test your implementations.

I need JAVA code that's able to run.

Answer 1

Array Implementation:

create a class file named as 'ArrayImplementation .java' then copy and paste the below code and run it

import java.util.Scanner;

public class ArrayImplementation {
   static int SIZE = 5;
   static String list[] = new String[SIZE];
   static int end=0;
   static Scanner input = new Scanner(System.in);

   public static void main(String[] args) {
       int choice;
       while(true) {
           System.out.println("Enter the Corresponding number of your choices below :");
           System.out.println("1.Insert at Front\n2.Insert at Rear\n3.Remove particular element\n4.Print all Names\n5.Exit");
           choice = input.nextInt();
           if(choice==5) {
               System.out.println("Exited....");
               break;
           }
           switch(choice) {
               case 1:
                   insertFront();
                   break;
               case 2:
                   insertRear();
                   break;
               case 3:
                   removeParticular();
                   break;
               case 4:
                   printAll();
                   break;
               default:
                   System.out.println("Invalid Input");
                   break;
           }
       }
   }
   static String getNameFromUser() {
       System.out.println("Enter the name : ");
       String name = input.next();
       return name;
   }
   static void insertRear() {
       if(end<SIZE) {
           String name = getNameFromUser();
           list[end++] = name;
       }
       else
           System.out.println("Array is Full");
   }
   static void insertFront() {
       if(end<SIZE) {
           String name = getNameFromUser();
           for(int i=end;i>0;i--) {
               list[i]=list[i-1];
           }
           list[0] = name;
           end++;
       }
       else
           System.out.println("Array is Full");
   }
   static void removeParticular() {
       boolean found = false;
       if(end!=0) {
           String name = getNameFromUser();
           for(int i=end-1;i>=0;i--) {
               if(list[i].equalsIgnoreCase(name)) {
                   for(int j=i;j<end-1;j++) {
                       list[j] = list[j+1];
                   }
                   end--;
                   found = true;
                   System.out.println(name + " is removed from the Array");
                   break;
               }
           }
           if(!found)
               System.out.println(name + " is not found in the Array");
       }else
           System.out.println("Array is empty");
   }
   static void printAll() {
       if(end!=0) {
           int i;
           for(i=0;i<end-1;i++)
               System.out.print(list[i]+"->");
           System.out.println(list[i]);
       }
       else
           System.out.println("Array is empty");
   }
}

LinkedList:

create a class file named as 'LinkedList .java' then copy and paste the below code and run it

import java.util.Scanner;

class Node
{
protected String data;
protected Node link;
public Node()
{
link = null;
data = null;
}
public Node(String d,Node n)
{
data = d;
link = n;
}
public void setLink(Node n)
{
link = n;
}
public void setData(String d)
{
data = d;
}
public Node getLink()
{
return link;
}
public String getData()
{
return data;
}
}
public class LinkedList
{
protected Node start;
protected Node end ;
public int size ;

public LinkedList()
{
start = null;
end = null;
size = 0;
}
public boolean isEmpty()
{
return start == null;
}
public int getSize()
{
return size;
}
public void insertAtStart(String val)
{
Node nptr = new Node(val, null);
size++ ;
if(start == null)
{
start = nptr;
end = start;
}
else
{
nptr.setLink(start);
start = nptr;
}
}
public void insertAtEnd(String val)
{
Node nptr = new Node(val,null);
size++ ;
if(start == null)
{
start = nptr;
end = start;
}
else
{
end.setLink(nptr);
end = nptr;
}
}
public void deleteAtPos(int pos)
{
if (pos == 1)
{
start = start.getLink();
size--;
return ;
}
if (pos == size)
{
Node s = start;
Node t = start;
while (s != end)
{
t = s;
s = s.getLink();
}
end = t;
end.setLink(null);
size --;
return;
}
Node ptr = start;
pos = pos - 1 ;
for (int i = 1; i < size - 1; i++)
{
if (i == pos)
{
Node tmp = ptr.getLink();
tmp = tmp.getLink();
ptr.setLink(tmp);
break;
}
ptr = ptr.getLink();
}
size-- ;
}
public void display()
{
System.out.print("\nSingly Linked List = ");
if (size == 0)
{
System.out.print("empty\n");
return;
}
if (start.getLink() == null)
{
System.out.println(start.getData() );
return;
}
Node ptr = start;
System.out.print(start.getData()+ "->");
ptr = start.getLink();
while (ptr.getLink() != null)
{
System.out.print(ptr.getData()+ "->");
ptr = ptr.getLink();
}
System.out.print(ptr.getData()+ "\n");
}
public static void main(String[] args)
{   
Scanner scan = new Scanner(System.in);
LinkedList list = new LinkedList();
System.out.println("Enter the Corresponding number of your choices below :");
char ch;
while(true)
{
System.out.println("1. Insert at front");
System.out.println("2. Insert at rear");
System.out.println("3. Delete at position");
System.out.println("4. Print All");
System.out.println("5. Exit");
int choice = scan.nextInt();
if(choice==5) {
               System.out.println("Exited....");
               break;
           }
switch (choice)
{
case 1 :
System.out.println("Enter the name:");
list.insertAtStart( scan.next() );   
break;
case 2 :
System.out.println("Enter the name:");
list.insertAtEnd( scan.next() );   
break;   
case 3 :
System.out.println("Enter position:");
int p = scan.nextInt() ;
if (p < 1 || p > list.getSize() )
System.out.println("Invalid position\n");
else
list.deleteAtPos(p);
break;
case 4:
   list.display();
   break;
default :
System.out.println("Invalid option \n ");
break;   
}   
}   
}
}

ScreenShots:

Note:

These code are created and verified on the Eclipse IDE,you can use any IDE to run the Code.

Hope this will help you to learn more.Happy Learning!!!