Question

What is the output of the first and second print statements?

import java.util.ArrayList;

public class addExample
{
public static void main(String[] args) {
ArrayList num1 = new ArrayList ();
ArrayList num2 = new ArrayList ();
num1.add(2);
num1.add(4);

num2.add(10);
num2.add(20);

System.out.println(num1.get(0)+1);
System.out.println(num1.get(1)+ num2.get(0));

}
}

The output of the first print statement is (blank)

and the output of the second statement is (blank).

Answer 1

The answer to this question is given below in the explanation section.

Step-by-step explanation:

When you will run the given code of java in this question. You will get an error and nothing will get printed in the response of the result. Because, in Java, you can't add the two array objects. The reason behind it, java does not support operator overloading. You cannot use the plus operator to add two arrays in Java . It will give you the compile-time error.

There is a method to add two arrays in the Java program is to iterate over them and add individual elements and store them into a new array. This also becomes complex, if you having arrays of different sizes. To go through this method, you have to build a method that will through an illegal exception in case of a mismatch in the sizes of the arrays.

As in the given code, when you execute the first print statement:

System.out.println(num1.get(0)+1);

It will produce error because first type is object and second is int. So, you cannot add object and int value.

When you will execute the given second print statement:

System.out.println(num1.get(1)+ num2.get(0));

it will also produce error, because you cannot add object in Java using + binary operator because in this statement first and second type are both objects.