Question

java

write a method to to find the negative numbers in L1 and L2 (linked list) and put them in L3 .

Answer 1

import java.util.Iterator;

import java.util.LinkedList;
import java.util.Random;

public class ListDemo {
  
   private static LinkedList<Integer> L1;           // Defining L1 as LinkedList of Integers
   private static LinkedList<Integer> L2;           // Defining L2 as LinkedList of Integers
   private static LinkedList<Integer> L3;           // Defining L3 as LinkedList of Integers

  
   /*
   * main method to
   * 1. populate the lists (L1 and L2) with random positive and negative numbers
   *       extract negative numbers from L1 and L2 and putting them in L3
   * 2. print L1, L2 and L3
   */
   public static void main(String[] args) {
       L1 = new LinkedList<Integer>();               //Instantiating L1
       L2 = new LinkedList<Integer>();               //Instantiating L2  
      
       L3 = new LinkedList<Integer>();               //Instantiating L3
      
       popualateLists(L1, L2, L3);
      
       printLists(L1, L2, L3);
   }

  
   /*
   * method to populate the lists (L1 and L2) with random positive and negative numbers and add the
   * negative numbers from them to L3
   */
   private static void popualateLists(LinkedList<Integer> L1, LinkedList<Integer> L2, LinkedList<Integer> L3) {
      
       //populate the lists (L1 and L2) with random positive and negative numbers
       Random random = new Random();
       for (int i = 0; i < 10 ; i++) {
           L1.add(random.nextInt(50) * (random .nextBoolean() ? -1 : 1));
           L2.add(random.nextInt(50) * (random .nextBoolean() ? -1 : 1));
       }
      
      
      
       //extract negative numbers from L1 and L2 and putting them in L3
       Iterator<Integer> iterator1 = L1.iterator();
       Iterator<Integer> iterator2 = L2.iterator();
      
       //adding negative numbers from L2 to L3
       Integer num;
       while (iterator1.hasNext()) {
           num = iterator1.next().intValue();
           if(num < 0) {
               L3.add(num);
           }
       }
      
       //adding negative numbers from L2 to L3
       while (iterator2.hasNext()) {
           num = iterator2.next().intValue();
           if(num < 0) {
               L3.add(num);
           }
       }
   }

   //method to print L1, L2 and L3 for testing purpose
   private static void printLists(LinkedList<Integer> L1, LinkedList<Integer> L2, LinkedList<Integer> L3) {
      
       Iterator<Integer> iteratorl1 = L1.iterator();
       Iterator<Integer> iteratorl2 = L2.iterator();
       Iterator<Integer> iteratorl3 = L3.iterator();
      
       // printing L1
       System.out.println("Numbers in L1: ");
       while (iteratorl1.hasNext()) {
           System.out.print(iteratorl1.next().intValue() + " ");
          
       }
      
       // printing L2
       System.out.println("\n\nNumbers in L2: ");
       while (iteratorl2.hasNext()) {
           System.out.print(iteratorl2.next().intValue() + " ");
       }
      
       // printing L3
       System.out.println("\n\nNumbers in L3 after putting negative numbers from L1 and L2 : ");
       while (iteratorl3.hasNext()) {
           System.out.print(iteratorl3.next().intValue() + " ");
       }
   }
}

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