linkedlist add done

Author: Ram swaroop

src/me/ramswaroop/Main.java

@@ -1,9 +1,7 @@
 package me.ramswaroop;
 
-import me.ramswaroop.common.LinkedQueue;
-import me.ramswaroop.common.LinkedStack;
-import me.ramswaroop.common.Queue;
-import me.ramswaroop.common.Stack;
+import me.ramswaroop.common.*;
+import me.ramswaroop.linkedlists.SingleLinkedList;
 
 import java.util.Scanner;
 
@@ -16,13 +14,14 @@ public static void main(String[] args) {
         Scanner in = new Scanner(System.in);
         Stack<Integer> stack = new LinkedStack<>();
         Queue<Integer> queue = new LinkedQueue<>();
+        LinkedList<Integer> singleLinkedList = new SingleLinkedList<>();
         chooseModule:
         while (true) {
             out.println("Choose module:");
             out.println("==============");
             out.println("1. Stack");
             out.println("2. Queue");
-            out.println("3. BST");
+            out.println("3. SingleLinkedList");
             out.println("4. Exit");
             k1 = Integer.parseInt(in.nextLine());
             switch (k1) {
@@ -95,7 +94,34 @@ public static void main(String[] args) {
                         }
                     }
                 case 3:
-                    break;
+                    while (true) {
+                        out.println("Select operation:");
+                        out.println("=================");
+                        out.println("1. Add");
+                        out.println("2. Remove");
+                        out.println("3. Print");
+                        out.println("4. Exit module");
+                        k2 = Integer.parseInt(in.nextLine());
+                        switch (k2) {
+                            case 1:
+                                out.println("Enter value:");
+                                int input = Integer.parseInt(in.nextLine());
+                                singleLinkedList.add(input);
+                                singleLinkedList.printList();
+                                break;
+                            case 2:
+                                out.println("Removed element: " + singleLinkedList.remove());
+                                singleLinkedList.printList();
+                                break;
+                            case 3:
+                                singleLinkedList.printList();
+                                break;
+                            case 5:
+                                continue chooseModule;
+                            default:
+                                out.println("Wrong choice!");
+                        }
+                    }
                 case 4:
                     out.println("Exiting...");
                     System.exit(0);

src/me/ramswaroop/common/LinkedList.java

@@ -13,7 +13,7 @@ public interface LinkedList<E> {
      * Appends the specified element to the end of this list.
      *
      * @param item
-     * @return
+     * @return {@code true} (as specified by {@link java.util.Collection#add})
      */
     boolean add(E item);
 
@@ -86,6 +86,11 @@ public interface LinkedList<E> {
      */
     E getLast();
 
+    /**
+     * Prints the contents of this list.
+     */
+    void printList();
+
     /**
      * Retrieves and removes the head (first element) of this list.
      *

src/me/ramswaroop/linkedlists/DoubleLinkedList.java

@@ -2,6 +2,8 @@
 
 import me.ramswaroop.common.LinkedList;
 
+import static java.lang.System.out;
+
 /**
  * Created by IntelliJ IDEA.
  *
@@ -11,6 +13,8 @@
  */
 public class DoubleLinkedList<E> implements LinkedList<E> {
 
+    Node<E> head;
+
     @Override
     public boolean add(E item) {
         return false;
@@ -85,4 +89,39 @@ public E set(int index, E item) {
     public int size() {
         return 0;
     }
+
+    @Override
+    public void printList() {
+        Node<E> curr = head;
+        out.print("[");
+        if (curr == null) {
+            out.println("]");
+            return;
+        }
+        while (curr.next != null) {
+            out.print(curr.item + ",");
+            curr = curr.next;
+        }
+        out.println(curr.item + "]");
+    }
+
+    private class Node<E> {
+        E item;
+        Node<E> next;
+        Node<E> prev;
+
+        Node(Node<E> prev, E item, Node<E> next) {
+            this.item = item;
+            this.next = next;
+            this.prev = prev;
+        }
+
+        Node(Node<E> node) {
+            if (node == null) return;
+
+            this.item = node.item;
+            this.next = node.next;
+            this.prev = node.prev;
+        }
+    }
 }

src/me/ramswaroop/linkedlists/SingleLinkedList.java

@@ -2,6 +2,8 @@
 
 import me.ramswaroop.common.LinkedList;
 
+import static java.lang.System.out;
+
 /**
  * Created by IntelliJ IDEA.
  *
@@ -11,9 +13,23 @@
  */
 public class SingleLinkedList<E> implements LinkedList<E> {
 
+    Node<E> head;
+    int size;
+
     @Override
     public boolean add(E item) {
-        return false;
+        Node<E> newNode = new Node<>(item, null);
+        if (head == null) {
+            head = newNode;
+        } else {
+            Node<E> curr = head;
+            while (curr.next != null) {
+                curr = curr.next;
+            }
+            curr.next = newNode;
+        }
+        size++;
+        return true;
     }
 
     @Override
@@ -83,6 +99,38 @@ public E set(int index, E item) {
 
     @Override
     public int size() {
-        return 0;
+        return size;
+    }
+
+    @Override
+    public void printList() {
+        Node<E> curr = head;
+        out.print("[");
+        if (curr == null) {
+            out.println("]");
+            return;
+        }
+        while (curr.next != null) {
+            out.print(curr.item + ",");
+            curr = curr.next;
+        }
+        out.println(curr.item + "]");
+    }
+
+    private class Node<E> {
+        E item;
+        Node<E> next;
+
+        Node(E item, Node<E> next) {
+            this.item = item;
+            this.next = next;
+        }
+
+        Node(Node<E> node) {
+            if (node == null) return;
+
+            this.item = node.item;
+            this.next = node.next;
+        }
     }
 }