Answer:
The code will give an error that is "At least one public class is required in main file".
Explanation:
In the given code if we do not use the public access modifier to the class. It will give an error so, the correct code to this question as follows:
Program:
import java.util.HashSet; //import package
public class A //define class as public.
{
public static void main(String[ ] args) //define main method.
{
HashSet set = new HashSet(); //creating hashset object.
set.add("A"); //add alphabet in hashset
set.add("B"); //add alphabet in hashset
set.add("C"); //add alphabet in hashset
System.out.print("Size of HashSet is :"set.size()); //print the size of hashset.
}
}
Output:
Size of HashSet is : 3
Explanation of the program:
- In the above program, we define a public class that is "A" and inside the class, we define the main method.
- Inside the main method, we create a HashSet class object that is "set".
- To add elements in HashSet we use add() function that adds elements and in the last, we use the size() function that prints the size HashSet.
Answer:
It we were asked to develop a new data compression tool, it is recommended to use Huffman coding since it is easy to implement and it is widely used.
Explanation:
The pros and the cons of Huffman coding
Huffman coding is one of the most simple compressing encoding schemes and can be implemented easily and efficiently. It also has the advantage of not being patented like other methods (e.g. arithmetic codingfor example) which however are superior to Huffman coding in terms of resulting code length.
One thing not mentioned so far shall not be kept secret however: to decode our 96 bit of “brief wit” the potential receiver of the bit sequence does need the codes for all letters! In fact he doesn’t even know which letters are encoded at all! Adding this information, which is also called the “Huffman table” might use up more space than the original uncompressed sentence!
However: for longer texts the savings outweigh the added Huffman table length. One can also agree on a Huffman table to use that isn’t optimized for the exact text to be transmitted but is good in general. In the English language for example the letters “e” and “t” occur most often while “q” and “z” make up the least part of an average text and one can agree on one Huffman table to use that on average produces a good (=short) result. Once agreed upon it doesn’t have to be transmitted with every encoded text again.
One last thing to remember is that Huffman coding is not restricted to letters and text: it can be used for just any symbols, numbers or “abstract things” that can be assigned a bit sequence to. As such Huffman coding plays an important role in other compression algorithms like JPG compression for photos and MP3 for audio files.
The pros and the cons of Lempel-Ziv-Welch
The size of files usually increases to a great extent when it includes lots of repetitive data or monochrome images. LZW compression is the best technique for reducing the size of files containing more repetitive data. LZW compression is fast and simple to apply. Since this is a lossless compression technique, none of the contents in the file are lost during or after compression. The decompression algorithm always follows the compression algorithm. LZW algorithm is efficient because it does not need to pass the string table to the decompression code. The table can be recreated as it was during compression, using the input stream as data. This avoids insertion of large string translation table with the compression data.
Answer:
Folksonomy.
Explanation:
A system of classifying and organizing online content into categories by the use of user-generated metadata such as keywords is called a folksonomy.
This ultimately implies that, folksonomy is a user-generated system which is typically used for classifying and organizing online content into various categories through the use of metadata such as keywords, electronic tags and public tags in order to make it easier to find in the future.
Hence, folksonomy is highly beneficial in areas such as collaborative learning, teacher resource repository, collaborative research, educational platforms, e-commerce etc.
Answer:
The correct option to the following question is option A.
Explanation:
Traditional database system is also known as the data warehouses and the relational database system which have been primary way organizations and the businesses have analyzed and stored their data and information for past 20 to 50 years. Traditional application of database systems are designed from ground up to the work with the data that has the primarily structured data.
A Web database or a browser-based database is the database application which is designed for accessed and managed from the Internet. Website or browser operators can be manage the collection of present analytical results-based and data on the data in the Browser-based database application.
Answer: rootkit
Explanation:
Hi, A rootkit is a collection of computer software, typically malicious, designed to enable access to a computer or an area of its software that is not otherwise allowed (for example, to an unauthorized user) and often masks its existence or the existence of other software.
A rootkit provides continued privileged access to a computer while hiding its presence. Because of this hiding characteristic it is very difficult to detect.
Once a rootkit has been installed, it allows someone to have total remote control of a computer and do things such as files executions and system changes.
