Question

Write a Java program to initialize an array with the even integers from 2 to 20 and print the result then pass this array to a method in order to create a new array which is the inverse of the array you passed (print the result).
You cannot use a third array.
Insert comments and version control in the program to document the program.

Answer 1

public class Main
{
//method to reverse the array
public static void reverse(int arr[], int size)
{
//variable declaration
int temp;
  
//reverse the array
for(int i=0; i<size/2; i++)
{
temp = arr[i];
arr[i] = arr[size-i-1];
arr[size-i-1] = temp;
}
}
  
   public static void main(String[] args)
   {
   //array declaration
       int array[] = new int[10];
      
       //variable declaration and initialization
       int i=0;
      
       //fill the array with even integer
       for(int value=2; value<=20; value++)
       {
       if(value%2==0)
       {
       array[i++] = value;
       }
       }
      
       //display message on the computer screen
       System.out.println("The array is: ");
      
       //display the array element on the computer screen
       for(int k=0; k<10; k++)
       {
       //display the element and one space after that
       System.out.print(array[k]+" ");
       }
      
       //method calling
       reverse(array, 10);
      
       //display the message on the computer screen
       System.out.println("\n\nThe reverse array is: ");
      
       //display the array element on the computer screen
       for(int k=0; k<10; k++)
       {
       //display the element and one space after that
       System.out.print(array[k]+" ");
       }
   }
}

OUTPUT:

The array is:
2 4 6 8 10 12 14 16 18 20

The reverse array is:
20 18 16 14 12 10 8 6 4 2