Data Structures: Arrays

Static Array

Array is a linear data structure where all elements are arranged sequentially. It is a collection of elements of same data type stored at contiguous memory locations.

Initialization

public class Array<t> {
    private T[] self;
    private int size;
    @SuppressWarnings("unchecked")
    public Array(int size) {
        if (size 



<p>In Core Array Class, we are going to store size of array and a general skeleton for array initialization. In constructor, we are asking for size of array and making an object and type casting it in our desired array.</p>

<h3>
  
  
  Set Method
</h3>



<pre class="brush:php;toolbar:false">public void set(T item, int index) {
        if (index >= this.size || index 



<p>This method is asking for an item to be stored in array and index on which item should be stored.</p>

<h3>
  
  
  Get Method
</h3>



<pre class="brush:php;toolbar:false">public T get(int index) {
        if (index >= this.size || index 



<p>Get Method asks for an index and retrives item from that index.</p>

<h3>
  
  
  Print Method
</h3>



<pre class="brush:php;toolbar:false">public void print() {
        for (int i = 0; i 



<p>Print Method is just printing all members of an array in a single line with a space seperating each item between them.</p>

<h2>
  
  
  Sorted Array
</h2>

<p>Arrays but having a functionality to sort elements itself.</p>

<h3>
  
  
  Initialization
</h3>



<pre class="brush:php;toolbar:false">public class SortedArray<t extends comparable>> {
    private T[] array;
    private int size;
    private final int maxSize;
    @SuppressWarnings("unchecked")
    public SortedArray(int maxSize) {
        if (maxSize 



<p>In Sorted Array Class, we are going to store size of array and ask for Max size of array as well and a general skeleton for array initialization. In constructor, we are asking for Max Size of array and making an object and type casting it in our desired array.</p>

<h3>
  
  
  Getters
</h3>



<pre class="brush:php;toolbar:false">public int length() {
        return this.size;
    }
 public int maxLength() {
        return this.maxSize;
    }
 public T get(int index) {
        if (index = this.size) {
            throw new IndexOutOfBoundsException("Index out of 
 bounds: " + index);
        }
        return this.array[index];
    }

Insertion Method

private int findInsertionPosition(T item) {
        int left = 0;
        int right = size - 1;
        while (left = this.maxSize) {
            throw new IllegalStateException("The array is already full");
        }

        int position = findInsertionPosition(item);

        for (int i = size; i > position; i--) {
            this.array[i] = this.array[i - 1];
        }
        this.array[position] = item;
        size++;
    }

Insert Method inserts the item on its position in sorted form.

Deletion Method

    public void delete(T item) {
        int index = binarySearch(item);
        if (index == -1) {
            throw new IllegalArgumentException("Unable to delete element " + item + ": the entry is not in the array");
        }

        for (int i = index; i 



<h3>
  
  
  Search Methods
</h3>



<pre class="brush:php;toolbar:false">private int binarySearch(T target) {
        int left = 0;
        int right = size - 1;
        while (left 



<h3>
  
  
  Traverse Method
</h3>



<pre class="brush:php;toolbar:false">public void traverse(Callback<t> callback) {
        for (int i = 0; i 



<h3>
  
  
  Callback Interface
</h3>



<pre class="brush:php;toolbar:false">public interface Callback<t> {
        void call(T item);
    }
</t>

Use of Callback Interface in Traversing

public class UppercaseCallback implements UnsortedArray.Callback<string> {
    @Override
    public void call(String item) {
        System.out.println(item.toUpperCase());
    }
}
</string>

Unsorted Array

It is almost same from above
Initialization and getters are same.

Insertion Method

public void insert(T item) {
        if (this.size >= this.maxSize) {
            throw new IllegalStateException("The array is already full");
        } else {
            this.self[this.size] = item;
            this.size++;
        }
    }

Delete Method is also same

Search Method

public Integer find(T target) {
        for (int i = 0; i 



<h2>
  
  
  Dynamic Array
</h2>

<p>Dynamic Array are like array lists or lists.</p>

<h3>
  
  
  Initialization
</h3>



<pre class="brush:php;toolbar:false">public class DynamicArray<t> {
    private T[] array;
    private int size;
    private int capacity;

    @SuppressWarnings("unchecked")
    public DynamicArray(int initialCapacity) {
        if (initialCapacity 



<h3>
  
  
  Insert Method
</h3>



<pre class="brush:php;toolbar:false">private void resize(int newCapacity) {
        @SuppressWarnings("unchecked")
        T[] newArray = (T[]) new Object[newCapacity];
        for (int i = 0; i = capacity) {
            resize(2 * capacity);
        }
        array[size++] = item;
    }

Delete Method

public void delete(T item) {
        int index = find(item);
        if (index == -1) {
            throw new IllegalArgumentException("Item not found: " + item);
        }

        for (int i = index; i  1 && size 



<p>Everything else is same.<br>
Hope this helps in working with arrays. Good Luck!</p>


          

            
        

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