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‎README.md

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<li><a href="https://github.com/HarryDulaney/intro-to-java-programming/tree/master/ch_20"><strong>Chapter 20</strong></a> - Lists, Stacks, Queues, and Priority Queues</li><br>
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<li><a href="https://github.com/HarryDulaney/intro-to-java-programming/tree/master/ch_21"><strong>Chapter 21</strong></a> - Sets and Maps</li><br>
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<li><a href="https://github.com/HarryDulaney/intro-to-java-programming/tree/master/ch_22"><strong>Chapter 22</strong></a> - Developing Efficient Algorithms</li><br>
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<li><!--<a href="https://github.com/HarryDulaney/java-programming-daniel-liang-10th/tree/master/">--><strong>Chapter 23</strong><!--</a>--> - Sorting</li><br>
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<li><!--<a href="https://github.com/HarryDulaney/java-programming-daniel-liang-10th/tree/master/">--><strong>Chapter 24</strong><!--</a>--> - Implementing Lists, Stacks, Queues, and Priority Queues</li><br>
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<li><a href="https://github.com/HarryDulaney/intro-to-java-programming/tree/master/ch_23"><strong>Chapter 23</strong></a> - Sorting</li><br>
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<li><a href="https://github.com/HarryDulaney/java-programming-daniel-liang-10th/tree/master/ch_24"><strong>Chapter 24</strong></a> - Implementing Lists, Stacks, Queues, and Priority Queues</li><br>
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<li><a href="https://github.com/HarryDulaney/intro-to-java-programming/tree/master/ch_25"><strong>Chapter 25</strong></a> - Binary Search Trees </li><br>
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<li><!--<a href="https://github.com/HarryDulaney/java-programming-daniel-liang-10th/tree/master/">--><strong>Chapter 26</strong><!--</a>--> - AVL Trees </li><br>
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<li><!--<a href="https://github.com/HarryDulaney/java-programming-daniel-liang-10th/tree/master/">--><strong>Chapter 27</strong><!--</a>--> - Hashing</li><br>

‎ch_22/Exercise22_01.java

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* Time complexity is O(n^2).
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* As the length of the input grows, the time complexity will grow
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* exponentially because we use an inner loop to traverse each
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* sub-string of input string.
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* sub-string of the input string.
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*/
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public class Exercise22_01 {
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public static void main(String[] args) {

‎ch_24/exercise24_01/Exercise24_01.java

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package ch_24.exercise24_01;
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import java.util.ArrayList;
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import java.util.Arrays;
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import java.util.Iterator;
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import java.util.List;
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/**
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* 24.1 (Add set operations in MyList) Define the following methods in MyList and
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* implement them in MyAbstractList:
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* Adds the elements in otherList to this list.
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* Returns true if this list changed as a result of the call
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* public boolean addAll(MyList<E> otherList);
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* <p>
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* Removes all the elements in otherList from this list
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* Returns true if this list changed as a result of the call
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* <p>
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* public boolean removeAll(MyList<E> otherList);
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* <p>
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* Retains the elements in this list that are also in otherList
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* Returns true if this list changed as a result of the call
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* <p>
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* public boolean retainAll(MyList<E> otherList);
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* <p>
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* <p>
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* Write a test program that creates two MyArrayLists,list1 and list2, with
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* the initial values{"Tom","George","Peter","Jean","Jane"} and
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* {"Tom","George","Michael","Michelle","Daniel"},then perform the following operations:
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* ■ Invokes list1.addAll(list2),and displays list1 and list2.
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* ■ Recreates list1 and list2 with the same initial values,invokes
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* list1.removeAll(list2),and displays list1 and list2.
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* ■ Recreates list1 and list2 with the same initial values,invokes
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* list1.retainAll(list2),and displays list1 and list2.
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*/
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public class Exercise24_01 {
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private final static String[] LIST_ONE_INIT_VALS = {"Tom", "George", "Peter", "Jean", "Jane"};
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private final static String[] LIST_TWO_INIT_VALS = {"Tom", "George", "Michael", "Michelle", "Daniel"};
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public static void main(String[] args) {
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MyList<String> list1 = new MyArrayList<>(LIST_ONE_INIT_VALS);
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MyList<String> list2 = new MyArrayList<>(LIST_TWO_INIT_VALS);
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System.out.println("List 1 and List 2 initial values: ");
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System.out.println("list1: " + list1);
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System.out.println("list2: " + list2);
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System.out.println("list1.addAll(list2) result: ");
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list1.addAll(list2);
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System.out.println("list1: " + list1);
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System.out.println("list2: " + list2);
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list1 = new MyArrayList<>(LIST_ONE_INIT_VALS);
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list2 = new MyArrayList<>(LIST_TWO_INIT_VALS);
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System.out.println("list1.removeAll(list2) result: ");
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list1.removeAll(list2);
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System.out.println("list1: " + list1);
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System.out.println("list2: " + list2);
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list1 = new MyArrayList<>(LIST_ONE_INIT_VALS);
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list2 = new MyArrayList<>(LIST_TWO_INIT_VALS);
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System.out.println("list1.retainAll(list2) result: ");
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list1.retainAll(list2);
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System.out.println("list1: " + list1);
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System.out.println("list2: " + list2);
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}
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}

‎ch_24/exercise24_01/MyAbstractList.java

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package ch_24.exercise24_01;
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import java.util.Iterator;
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public abstract class MyAbstractList<E> implements MyList<E> {
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protected int size = 0; // The size of the list
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/**
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* Create a default list
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*/
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protected MyAbstractList() {
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}
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/**
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* Create a list from an array of objects
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*/
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protected MyAbstractList(E[] objects) {
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for (int i = 0; i < objects.length; i++)
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add(objects[i]);
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}
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/**
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* Add a new element at the end of this list
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*/
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@Override
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public void add(E e) {
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add(size, e);
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}
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/**
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* Return true if this list doesn't contain any elements
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*/
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@Override
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public boolean isEmpty() {
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return size == 0;
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}
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/**
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* Return the number of elements in this list
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*/
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@Override
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public int size() {
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return size;
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}
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/**
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* Remove the first occurrence of the element e
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* from this list. Shift any subsequent elements to the left.
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* Return true if the element is removed.
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*/
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@Override
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public boolean remove(E e) {
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if (indexOf(e) >= 0) {
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remove(indexOf(e));
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return true;
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} else
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return false;
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}
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/*--------------------------------------------- Exercise24_01 ---------------------------------------------------*/
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/**
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* Adds the elements in otherList to this list.
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* Returns true if this list changed as a result of the call
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*/
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@Override
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public boolean addAll(MyList<E> otherList) {
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int startSize = size;
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for (E e : otherList) {
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if (!contains(e)) {
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add(e);
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}
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}
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return size == startSize;
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}
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/**
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* Removes all the elements in otherList from this list
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* Returns true if this list changed as a result of the call
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*/
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@Override
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public boolean removeAll(MyList<E> otherList) {
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boolean changed = false;
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for (E e : otherList) {
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boolean removed = remove(e);
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if (removed) {
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changed = true;
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}
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}
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return changed;
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}
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/**
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* Retains the elements in this list that are also in otherList
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* Returns true if this list changed as a result of the call
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*/
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@Override
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public boolean retainAll(MyList<E> otherList) {
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boolean changed = false;
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for (E e : this) {
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if (!otherList.contains(e)) {
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remove(indexOf(e));
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changed = true;
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}
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}
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return changed;
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}
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}

‎ch_24/exercise24_01/MyArrayList.java

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package ch_24.exercise24_01;
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import java.util.Iterator;
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public class MyArrayList<E> extends MyAbstractList<E> {
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public static final int INITIAL_CAPACITY = 16;
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private E[] data = (E[]) new Object[INITIAL_CAPACITY];
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/**
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* Create a default list
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*/
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public MyArrayList() {
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}
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/**
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* Create a list from an array of objects
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*/
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public MyArrayList(E[] objects) {
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for (int i = 0; i < objects.length; i++)
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add(objects[i]); // Warning: don't use super(objects)!
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}
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@Override
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/** Add a new element at the specified index */
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public void add(int index, E e) {
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ensureCapacity();
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// Move the elements to the right after the specified index
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for (int i = size - 1; i >= index; i--)
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data[i + 1] = data[i];
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// Insert new element to data[index]
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data[index] = e;
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// Increase size by 1
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size++;
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}
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/**
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* Create a new larger array, double the current size + 1
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*/
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private void ensureCapacity() {
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if (size >= data.length) {
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E[] newData = (E[]) (new Object[size * 2 + 1]);
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System.arraycopy(data, 0, newData, 0, size);
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data = newData;
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}
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}
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@Override
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/** Clear the list */
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public void clear() {
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data = (E[]) new Object[INITIAL_CAPACITY];
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size = 0;
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}
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@Override
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/** Return true if this list contains the element */
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public boolean contains(E e) {
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for (int i = 0; i < size; i++)
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if (e.equals(data[i])) return true;
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return false;
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}
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@Override
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/** Return the element at the specified index */
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public E get(int index) {
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checkIndex(index);
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return data[index];
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}
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private void checkIndex(int index) {
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if (index < 0 || index >= size)
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throw new IndexOutOfBoundsException
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("index " + index + " out of bounds");
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}
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@Override
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/** Return the index of the first matching element
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* in this list. Return -1 if no match. */
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public int indexOf(E e) {
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for (int i = 0; i < size; i++)
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if (e.equals(data[i])) return i;
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return -1;
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}
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@Override
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/** Return the index of the last matching element
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* in this list. Return -1 if no match. */
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public int lastIndexOf(E e) {
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for (int i = size - 1; i >= 0; i--)
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if (e.equals(data[i])) return i;
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return -1;
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}
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@Override
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/** Remove the element at the specified position
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* in this list. Shift any subsequent elements to the left.
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* Return the element that was removed from the list. */
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public E remove(int index) {
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checkIndex(index);
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E e = data[index];
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// Shift data to the left
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for (int j = index; j < size - 1; j++)
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data[j] = data[j + 1];
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data[size - 1] = null; // This element is now null
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// Decrement size
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size--;
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return e;
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}
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@Override
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/** Replace the element at the specified position
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* in this list with the specified element. */
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public E set(int index, E e) {
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checkIndex(index);
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E old = data[index];
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data[index] = e;
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return old;
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}
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@Override
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public String toString() {
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StringBuilder result = new StringBuilder("[");
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for (int i = 0; i < size; i++) {
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result.append(data[i]);
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if (i < size - 1) result.append(", ");
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}
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return result.toString() + "]";
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}
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/**
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* Trims the capacity to current size
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*/
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public void trimToSize() {
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if (size != data.length) {
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E[] newData = (E[]) (new Object[size]);
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System.arraycopy(data, 0, newData, 0, size);
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data = newData;
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} // If size == capacity, no need to trim
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}
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@Override
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/** Override iterator() defined in Iterable */
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public java.util.Iterator<E> iterator() {
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return new ArrayListIterator();
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}
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private class ArrayListIterator
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implements java.util.Iterator<E> {
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private int current = 0; // Current index
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@Override
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public boolean hasNext() {
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return (current < size);
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}
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@Override
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public E next() {
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return data[current++];
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}
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@Override
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public void remove() {
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MyArrayList.this.remove(current);
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}
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}
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}

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