Question

Write a program that adds and subtracts two polynomials. It creates an array of nodes and connects them into the freeStore. This implementation uses one array to store multiple array to store multiple polynomial instances and the free store. I need help to finish the LinkedListInArrayPolynomial class.

Output should look like below:

Forth test is linked list of terms in an array.
linkInArray1 = 3x^11+4x^10+4x^4
linkInArray2 = 4x^19+5x^14-3x^12-78
sum of linkInArray1 and linkInArray2 = 4x^19+5x^14-3x^12+3x^11+4x^10+4x^4-78
linkInArray1 minus linkInArray2 = -4x^19-5x^14+3x^12+3x^11+4x^10+4x^4+78

The classes done are given below:

public interface PolynomialInterface {

PolynomialInterface add(PolynomialInterface other); // Effect: Adds value to owner of addPolynomial method.// Postcondition: Return value = this + value.

   PolynomialInterface subtract( PolynomialInterface other);

   // Effect: Subtracts value from owner of addPolynomial method. // Postcondition: Return value = this - value. void readPolynomial(); // Postcondition: polynomial read.

   String toString(); // Postcondition: polynomial converted to string. } }

public class PlynomialDemo {
   public static void main(String[] args) {
       // example strings constructor must handle
       // String s = "44";
       // String s = "44x";
       // String s = "4x^4+3x^3-3";
       // String s = "4x^3-3x^11";
       // String s = "44x^6-3x^10+4x^4";
       // String s = "25x^5-3x^13+4x^12-78";
       // String s ="34x^15-44x^14-3x^12+4x^31-78";
       // String s1 = "44";
       // String s2 = "44x-78";
       // String s1 = "4x^4+3x^3-3";
       // String s2 = "4x^6-3x^12";
//       String s1 = "4x^14-3x^12+4x^4+78";
//       String s2 = "-4x^4-3x^12+4x^17-78";
       String s1 = "4x^4+3x^11+4x^10";
       String s2 = "5x^14-3x^12+4x^19-78";
//       String s1 = "4x^5+4x^4-3x^12-4x^41-78";
//       String s2 = "-4x^4+3x^12+4x^41+78";
       System.out.println();
       PolynomialInterface linkInArray1 = new LinkedListInArrayPolynomial(s1);
       PolynomialInterface linkInArray2 = new LinkedListInArrayPolynomial(s2);
       PolynomialInterface linkInArray3 = new LinkedListInArrayPolynomial();
       System.out.println("Forth test is linked list of terms in an array.");
       // System.out.println("linkInArray1 string is " + s1);
       System.out.println("linkInArray1 = " + linkInArray1);
       // System.out.println("linkInArray2 string is " + s2);
       System.out.println("linkInArray2 = " + linkInArray2);
       linkInArray3 = linkInArray1.add(linkInArray2);
       System.out.println("sum of linkInArray1 and linkInArray2 = " + linkInArray3);
       linkInArray3 = linkInArray1.subtract(linkInArray2);
       System.out.println("linkInArray1 minus linkInArray2 = " + linkInArray3); } }

public class LLInArrayNode implements Comparable {
   private int NUL = -1;
   private String value;
   private int next;

   public LLInArrayNode() {
   }

   public LLInArrayNode(LLInArrayNode node) {
       this.value = node.value;
       this.next = node.next;
   }

   public LLInArrayNode(String value) {
       this.value = value;
       this.next = NUL;
   }

   public LLInArrayNode(String value, int next) {
       this.value = value;
       this.next = next;
   }

   public int compareTo(LLInArrayNode other) {
//calls the String compareToIgnoreCase() method
       return this.value.compareToIgnoreCase(other.value);
   }

   public String getValue() {
       return value;
   }

   public void setValue(String value) {
       this.value = value;
   }

   public int getNext() {
       return next;
   }

   public void setNext(int next) {
       this.next = next;
   }

   public String toString() {
       return "Value = " + value + " " + " next " + next;
   }
}

public class LinkedListInArrayPolynomial implements PolynomialInterface {
   private static final int NUL = -1;
   private static int free; // *** Reference to the first node on the free list
   private static LLInArrayNode[] nodeArray = new LLInArrayNode[1000];
   private static boolean nodeArrayIsInitialized = false;
   private String polyString;
   private int polynomial = NUL; // *** Reference to the first node on the list
   public LinkedListInArrayPolynomial(){
       if (!nodeArrayIsInitialized)
           initializeStaticArray();
   }
   public LinkedListInArrayPolynomial(String polyString){
       if (!nodeArrayIsInitialized)
           initializeStaticArray();
       this.polyString(polyString);
       storePolynomial();
   }
   private void initializeStaticArray(){
       // fill array with nodes
       for (int x = 0; x < nodeArray.length; x++){
           nodeArray[x] = new LLInArrayNode();
       }
       for (int index = 1; index < nodeArray.length; index++){
           nodeArray[index - 1].setNext(index);
       }
       nodeArray[nodeArray.length - 1].setNext(NUL);
       free = 0;
       nodeArrayIsInitialized = true;
   }
   protected int getNode()
   // *** Returns the index of the next available node from the freeStore
   // *** and updates the freeStore index.
   {
       int hold;
       hold = free;
       free = nodeArray[free].getNext();
       return hold;
   }
   @Override
   public PolynomialInterface add(PolynomialInterface other) {
       // TODO Auto-generated method stub
       return null;
   }

   @Override
   public PolynomialInterface subtract(PolynomialInterface other) {
       // TODO Auto-generated method stub
       return null;
   }
}

Answer 1

Check it. I hope it could work for you. give feedback please.

public interface PolynomialInterface

{

PolynomialInterface add(PolynomialInterface other);

// Effect: Adds value to owner of addPolynomial method.

// Postcondition: Return value = this + value.

PolynomialInterface subtract(PolynomialInterface other);

// Effect: Subtracts value from owner of addPolynomial method.

// Postcondition: Return value = this - value. void readPolynomial();

// Postcondition: polynomial read.

String toString();

// Postcondition: polynomial converted to string.

}

#### Imp...#### It should Create and array or ArrayList of nodes, each node holding a term of the polynomial

Your code must use the Demo provided below.

public class PlynomialDemo
{
        public static void main(String[] args)
        {
                // example strings constructor must handle
                //      String s = "44";
                //      String s = "44x";
                //      String s = "4x^4+3x^3-3";
                //      String s = "4x^3-3x^11";
                //      String s = "44x^6-3x^10+4x^4";
                //      String s = "25x^5-3x^13+4x^12-78";
                //      String s ="34x^15-44x^14-3x^12+4x^31-78";
                //      String s1 = "44";
                //      String s2 = "44x-78";
                //      String s1 = "4x^4+3x^3-3";
                //      String s2 = "4x^6-3x^12";
                String s1 = "4x^14-3x^12+4x^4+78";
                String s2 = "-4x^4-3x^12+4x^17-78";
                //      String s1 = "4x^4+3x^11+4x^10";
                //      String s2 = "5x^14-3x^12+4x^19-78";
                //  String s1 = "4x^5+4x^4-3x^12-4x^41-78";
                //  String s2 = "-4x^4+3x^12+4x^41+78";


                

PolynomialInterface sortA1 = new ArraySortedPolynomial(s1);
                PolynomialInterface sortA2 = new ArraySortedPolynomial(s2);
                PolynomialInterface sortA3; 
                sortA3 = sortA1.add(sortA2);
                System.out.println("Second test is sorted array of terms.");
                //      System.out.println("sortA1 string is           " + s1);
                System.out.println("sortA1 =                   " + sortA1);
                //      System.out.println("sortA2 string is           " + s2);
                System.out.println("sortA2 =                   " + sortA2);
                System.out.println("sortA3 = sortA1.add(sortA2)      " + sortA3);
                sortA3 = sortA1.subtract(sortA2);
                //      System.out.println("sortA1 string is           " + s1);
                //System.out.println("sortA1 =                   " + sortA1);
                //      System.out.println("sortA2 string is           " + s2);
                //System.out.println("sortA2 =                   " + sortA2);
                System.out.println("sortA3 = sortA1.subtract(sortA2) " + sortA3);
                System.out.println();

       }
}