2nd Ex Finished

.idea/ds_exercises.iml

@@ -0,0 +1,9 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<module type="JAVA_MODULE" version="4">
+  <component name="NewModuleRootManager" inherit-compiler-output="true">
+    <exclude-output />
+    <content url="file://$MODULE_DIR$" />
+    <orderEntry type="inheritedJdk" />
+    <orderEntry type="sourceFolder" forTests="false" />
+  </component>
+</module>

sll/.idea/vcs.xml

@@ -0,0 +1,6 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project version="4">
+  <component name="VcsDirectoryMappings">
+    <mapping directory="$PROJECT_DIR$/.." vcs="Git" />
+  </component>
+</project>

sll/src/main/java/com/tabrizu/ds/App.java

@@ -4,16 +4,24 @@ package com.tabrizu.ds;
  * Hello world!
  */
 public final class App {
-    private App() {
-    }
-
-    /**
-     * Says hello to the world.
-     * @param args The arguments of the program.
-     */
     public static void main(String[] args) {
         System.out.println("Hello World!");
+        SingleLinkedList<Integer> list = new SingleLinkedList<Integer>();
+        System.out.println("Step 0: " + list);
+        list.addLast(55);
+        list.addLast(76);
+        list.addLast(35);
+        list.addFirst(22);
+        System.out.println("Step 1: " + list);
+        System.out.println("[Remove]: " + list.removeLast());
+        System.out.println("Step 2: " + list);
+        list.addFirst(78);
+        list.addLast(88);
+        System.out.println("Step 3: " + list);
+        System.out.println("[Remove]: " + list.removeFirst());
+        System.out.println("Step 4: " + list);
+        System.out.println("First: " + list.getFirst());
+        System.out.println("Last: " + list.getLast());
 
-        SingleLinkedList<Integer> myList = new SingleLinkedList<Integer>();
     }
 }

sll/src/main/java/com/tabrizu/ds/SingleLinkedList.java

@@ -1,5 +1,4 @@
 package com.tabrizu.ds;
-
 public class SingleLinkedList<T> implements ISingleLinkedList<T> {
 
     private class Node {
@@ -46,17 +45,21 @@ public class SingleLinkedList<T> implements ISingleLinkedList<T> {
             m_tail = m_head;
         }
         m_size += 1;
+        System.out.println("First Node added with value: " + value);
+
     }
 
     @Override
     public void addLast(T value) {
         if (m_size == 0) {
             addFirst(value);
+            return;
         }
         Node newNode = new Node(value, null);
         m_tail.setNext(newNode);
         m_tail = newNode;
         m_size++;
+        System.out.println("Last Node added with value: " + value);
 
     }
 
@@ -77,30 +80,50 @@ public class SingleLinkedList<T> implements ISingleLinkedList<T> {
         if (m_size == 0) {
             return null;
         }
+        if (m_size == 1) {
+            removeFirst();
+        }
         T lastTail = m_tail.getValue();
         Node currentNode = m_head;
-        while (currentNode.getNext() != null){
+        while (currentNode.getNext().getNext() != null){
-
             currentNode = currentNode.getNext();
-
         }
+        m_tail = currentNode;
+        m_tail.setNext(null);
+        m_size--;
+        return lastTail;
     }
 
     @Override
     public T getFirst() {
-        // TODO Auto-generated method stub
+        if (m_size == 0){
-        return null;
+            return null;
+        }
+        return m_head.getValue();
     }
 
     @Override
     public T getLast() {
-        // TODO Auto-generated method stub
+        if (m_size == 0) {
-        return null;
+            return null;
+        }
+        return m_tail.getValue();
     }
 
     @Override
     public String toString() {
-
+        if (m_size == 0){
+            return "[NULL]";
+        }
+        Node currentNode = m_head;
+        StringBuilder output = new StringBuilder();
+        while (currentNode != null){
+            output.append(currentNode.getValue());
+            if (currentNode.getNext() != null)
+                output.append(" => ");
+            currentNode = currentNode.getNext();
+        }
+        return output.toString();
     }
 
 }