Question

Write a Java class, named MultProgression, as a subclass of the Progression class, so that: • Each value in the progression is equal to the multiplication of the previous two values x[n] = x[n - 1] - x[n - 2] • Include a default constructor that starts with 1 and 2 as the first two values, Include a parametric constructor that starts with a specified pair of numbers as the first two values. • Write a test code, TestProgression, which prints first 10 values of the progression for initial values of 3 and 5.

Answer 1

Solution:

1.Create Progression class with two constructors: one is default constructor, it initializes the first two elements of progression as 1,2

2.Also create a parameterized constructor that can initialize the first two elements of the progression with specified values .

3. create a method testProgression() that constructs remaining values and prints 10 values of the progression

4.create MultiProgression class as a subclass for Progression

5.create the Default constructor in MultiProgression class and call super class constructor using super keyword. Do the same thing for Parameterized constructor

6.create the main method in MultiProgression class and create object for MultiProgression class and call the methods testProgression()

Java Program:

class Progression
{
int x[];
   Progression()
   {
   x=new int[10];
   x[0]=1;
   x[1]=2;
   }
   Progression(int first,int second)
   {
   x=new int[10];
   x[0]=first;
   x[1]=second;
   }

   public void testProgression()
   {
   int i;
   for( i=2;i<=9;i++)
      {
       x[i]=x[i-1]+x[i-2];
       }
   for(i=0;i<10;i++)
       {
       System.out.println(x[i]);
       }
   }
}
class MultiProgression extends Progression
{
   MultiProgression()
   {
   super();
   }

   MultiProgression(int first,int second)
   {
   super(first,second);
   }
  
   public static void main(String args[])
   {
   MultiProgression mp=new MultiProgression(3,5);
   mp.testProgression();
   }
}

OUTPUT:

D:\Java\jdk-10.0.2\bin>javac MultiProgression.java

D:\Java\jdk-10.0.2\bin>java MultiProgression
3
5
8
13
21
34
55
89
144
233