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Java Collection, HashSet Exercises: Test a hash set is empty or not

Java Collection, HashSet Exercises: Exercise-5 with Solution

Write a Java program to test a hash set is empty or not.

Sample Solution:

Java Code:

import java.util.*;

  public class Exercise5 {
  public static void main(String[] args) {
         // Create a empty hash set
     HashSet<String> h_set = new HashSet();
   // use add() method to add values in the hash set
          h_set.add("Red");
          h_set.add("Green");
          h_set.add("Black");
          h_set.add("White");
          h_set.add("Pink");
          h_set.add("Yellow");
    System.out.println("Original Hash Set: " + h_set);
    System.out.println("Checking the above array list is empty or not! "+h_set.isEmpty());
    System.out.println("Remove all the elements from a Hash Set: ");
    h_set.removeAll(h_set);
    System.out.println("Hash Set after removing all the elements "+h_set);   
   }
}

Sample Output:

Original Hash Set: [Red, White, Pink, Yellow, Black, Green]            
Checking the above array list is empty or not! false                   
Remove all the elements from a Hash Set:                               
Hash Set after removing all the elements [] 

Pictorial Presentation:

Java Collection, ArrayList Exercises: Test a hash set is empty or not

Flowchart:

Flowchart: Test a hash set is empty or not.

Java Code Editor:

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Java: Tips of the Day

Choice between Float and Double:

Data type Bytes used Significant figures (decimal)
Float 4 7
Double 8 15

Double is often preferred over float in software where precision is important because of the following reasons:
Most processors take nearly the same amount of processing time to perform operations on Float and Double. Double offers far more precision in the same amount of computation time.

Ref: https://bit.ly/3oj7K2K