in mess

pwenhua · pwenhua · commit 1f1276deefa2 · 2017-02-27T15:42:59.000-05:00
diff --git a/group20/2421586846/DS/.project b/group20/2421586846/DS/.project
@@ -0,0 +1,17 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<projectDescription>
+	<name>DS</name>
+	<comment></comment>
+	<projects>
+	</projects>
+	<buildSpec>
+		<buildCommand>
+			<name>org.eclipse.jdt.core.javabuilder</name>
+			<arguments>
+			</arguments>
+		</buildCommand>
+	</buildSpec>
+	<natures>
+		<nature>org.eclipse.jdt.core.javanature</nature>
+	</natures>
+</projectDescription>
diff --git a/group20/2421586846/DS/src/basic/LinkedList.java b/group20/2421586846/DS/src/basic/LinkedList.java
@@ -5,27 +5,49 @@ public class LinkedList implements List {
 	
 	private Node head;
 	
-	public void add(Object o){
+	private int size;
+	public void addError(Object o){
 		Node newNode= new Node();
 		newNode.data = o;
 		newNode.next = null;
 		
 		if (head == null ){
 			head= newNode;
+			size++;
+			return;
 		}
 		
 		Node currentNode = head;
+		/*
 		while (currentNode.next != null ){
 			currentNode = currentNode.next ; 
 		} 
-		
+		*/
+		for (int i=0;i< size;i++){
+			currentNode = currentNode.next ; 
+		}
 
 		currentNode.next =newNode;	
-			
+		size++;
+	}
+	public void add(Object o){
+		if (size==0) {
+			head=new Node();
+			head.data=o;
+			size++;
+			return;
+		}
+		Node last=head;
+		for (int i = 0; i < size-1; i++) {
+			last=last.next;
+		}
+		Node added=new Node();
+		last.next=added;
+		added.data=o;
+size++;
 	}
 	public void add(int index , Object o){
-		int oldSize = size();
-		if (index >= oldSize ||index < 0) {
+		if (index >= size ||index < 0) {
 			return;
 		}
 		
@@ -85,17 +107,8 @@ public Object remove(int index){
 	}
 	
 	public int size(){
-		if (head == null){
-			return 0;
-		}
 		
-		Node currentNode = head; 
-		int i =0;
-		while (currentNode.next != null){
-			currentNode =currentNode.next;
-			i++;
-		}
-		return i;
+		return size;
 	}
 	
 	public void addFirst(Object o){
@@ -104,7 +117,7 @@ public void addFirst(Object o){
 		newNode.next = head;
 		
 		head = newNode;
-		
+		size++;
 	}
 	public void addLast(Object o){
 		Node currentNode = head;
@@ -118,26 +131,29 @@ public void addLast(Object o){
 		newNode.next =null;
 		
 		currentNode.next = newNode;
-		
+		size++;
 	}
 	public Object removeFirst(){
+
+		size--;
 		if (head ==null){
 			return null;
 		}
 		else {
 			Node firstNode = head;
 			head = firstNode.next;	
 			return firstNode;
-		}
+		} 
 	}
 	public Object removeLast(){
-		int size = size();
+		
 		if (head ==null ){
 			return null;
 		}
 		if (size ==1){
 			Node tempnode = head;
 			head = null;
+			size--;
 			return tempnode.data;
 		}
 		Node currentNode = head.next;
@@ -149,8 +165,9 @@ public Object removeLast(){
 		}
 		PrevNode.next= null;
 		 
-		
+		size--;
 		return currentNode.data ;
+		
 	}
 	public Iterator iterator(){
 		return null;
diff --git a/group20/2421586846/DS/src/basic/Test.java b/group20/2421586846/DS/src/basic/Test.java
@@ -6,7 +6,22 @@
 public class Test {
 
 	public static void main(String[] args) {
-		
+		TestLinkedList();
+	
+	}
+	public static void TestLinkedList(){
+		LinkedList ll = new LinkedList();
+		ll.add(1);
+		ll.add(2);
+		ll.add(3);
+		int size = ll.size();
+		for (int i=0;i< size;i++){
+
+			System.out.println(ll.get(0));
+		}
+	}
+	
+	public static void TestArrayList(){
 		// TODO Auto-generated method stub
 		ArrayList arraylist1= new ArrayList();
 		arraylist1.add(3);
@@ -24,7 +39,14 @@ public static void main(String[] args) {
 		for (int i = 0 ;i <  arraylist1.size();i++){
 			System.out.println(arraylist1.get(i));
 		}
+		System.out.println("ok");
+		arraylist1.remove(0);
+
+		arraylist1.remove(1);
 		
+		for (int i = 0 ;i <  arraylist1.size();i++){
+			System.out.println(arraylist1.get(i));
+		}
 		/*
 	    int[] arr = {1,2,3,4,5};  
 	       
