Question

1. Implement the following methods. Assume that these will be methods within your myArray class.
   1. operator[]
      1. Should take in an int and return arr at that index if it is a valid index
   2. notEqual
      1. The notEqual should take in another myArray object and return true if the objects are not equal to one another and false if they are equal.
   3. operator-(float)
      1. Will subtract the float value that is passed in from each of the values in arr
   4. Copy constructor
      1. Will take in another myArray object and construct an object that is a copy of it.

Answer 1

Hi,

Hope yoou are doing fiine. I have coded the above question in java keepping all the given conditions in mind. The program has been clearly explained using comments that have been highlighted in bold. I have additionallly written tthe main method for checking the method and displayed some sample results.

Program:

public class myArray {
   //arr is attribute of class myArray which is an array of type float
   float [] arr;
  
   //constructor of myArray
   public myArray(float[] arr) {
       this.arr = arr;
   }
  
   //copy constructor
   public myArray(myArray b)
   {
       System.out.println("Copy constructor is called");
       //copying contents of current object to the passed object
       arr=b.arr;
   }
  
   //operator takes in an integer and returns array element at that position if valid
   public float operator(int index)
   {
       //if index is valid
       if(index>=0 && index<arr.length)
           return arr[index];
       return -1;
   }
  
   //method to check if two objects are equal
   public boolean notEqual(myArray b)
   {
       if(b.arr==this.arr)
           return false;
       return true;
   }
  
   //another operator method thaat takes in a float value and subtracts it from each element of arr
   public void operator(float num)
   {
       for(int i=0;i<this.arr.length;i++)
       {
           this.arr[i]-=num;
       }
   }
  
   //Main method to check all the above methods
   public static void main(String[] args) {
       // TODO Auto-generated method stub
       //declaring a float type array arr
       float [] arr= {1,2,8,9,6};
       //creating object a by passing arr as argument
       myArray a=new myArray(arr);
       //checking operator method
       float index=a.operator(3);
       if(index==-1)
           System.out.println("Not valid index");
       else
           System.out.println("Element at given index is: "+index);
       //declaring another array arr2
       float [] arr2= {100,101,193};
       //creating object b by passing arr2 as argument
       myArray b=new myArray(arr2);
       //checking notEqual method
       boolean res=a.notEqual(b);
       if(res)
           System.out.println("The objects are not equal");
       else
           System.out.println("The objects are equal");
       //Printing the array of object a before performing operator() method
       System.out.println("Contents of array before operator():");
       for(int i=0;i<a.arr.length;i++)
           System.out.println(a.arr[i]);
       System.out.println();
       //declaring f as a float number that is to be subtracted
       float f=1;
       //checking operator method. Here overloading occurs as there are two operator methods
       a.operator(f);
       System.out.println("Contents of array after operator():");
       for(int i=0;i<a.arr.length;i++)
           System.out.println(a.arr[i]);
       //declaring new object c and calling the copy constructor to construct it
       myArray c=new myArray(a);
       System.out.println("Contents of the copied object c:");
       //Printing contents of c
       for(int i=0;i<c.arr.length;i++)
           System.out.println(c.arr[i]);

   }

}

Executable code snippet:

Output: