Home/Groups/Learn Java

Group rules

Welcome to Learn JAVA! This group is dedicated to helping beginners and experienced developers alike master the Java programming language. See more
Welcome to Learn JAVA! This group is dedicated to helping beginners and experienced developers alike master the Java programming language. Whether you're just starting out or looking to enhance your skills, you'll find valuable resources, tutorials, and support from a community of passionate Java enthusiasts. Share your questions, tips, and projects, and let's code together towards a brighter future in Java development!

Group Rules for "Learn Java"

  1. Respect Everyone: Treat all members with respect and kindness. Any form of harassment, discrimination, or hate speech will not be tolerated.

  2. Stay On Topic: Keep discussions focused on Java programming. Off-topic posts may be removed to maintain the group's purpose.

  3. No Spam or Self-Promotion: Avoid posting spam, irrelevant links, or self-promotion without prior permission from the admins.

  4. Be Constructive: Provide helpful and constructive feedback. Avoid criticizing others’ questions or contributions negatively.

  5. No Plagiarism: Share original content or give proper credit when sharing others’ work. Plagiarism will lead to post removal and potential banning.

  6. Ask Clear Questions: When seeking help, provide as much detail as possible about your issue. Include code snippets, error messages, and what you've tried so far.

  7. Respect Privacy: Do not share personal information or private content without consent. Respect the privacy of all members.

  8. Use Appropriate Language: Keep the language professional and appropriate for a learning environment. Avoid using offensive or inappropriate language.

  9. Follow Admin Instructions: Admins and moderators are here to help maintain the group's integrity. Follow their guidance and respect their decisions.

  10. Report Issues: If you see any violations of these rules or have concerns, report them to the admins or moderators immediately.


By joining "Learn Java," you agree to abide by these rules and help create a supportive and productive learning environment for everyone. Happy coding!See less

Pankaj Gupta Scholar

3 months ago

Program to Check for A Disarium number

A Disarium number is a number where the sum of its digits powered with their respective positions is equal to the number itself. For example, 175 is a Disarium number because: 11+72+53=1+49+125=1751^1 + 7^2 + 5^3 = 1 + 49 + 125 = 175. Here’s a simple Java program to check if a number is a Disarium number: 

import java.util.Scanner; 
public class DisariumNumber 
  { // Method to calculate the number of digits in a number 
   public static int countDigits(int number) 
     { int count = 0; 
       while (number != 0) 
         { count++; 
           number /= 10; 
         } 
        return count; 
      } 

// Method to check if the number is Disarium 

public static boolean isDisarium(int number) 
  { int sum = 0, temp = number; 
    int digits = countDigits(number); 
    // Calculate sum of digits powered by their respective positions 
    while (temp != 0) 
      { int digit = temp % 10; 
        sum += Math.pow(digit, digits--); 
        temp /= 10; 
      } 
    // Return true if sum equals the original number 
    return sum == number; 
   } 
public static void main(String[] args) 
  { Scanner scanner = new Scanner(System.in); 
    System.out.print("Enter a number: "); 
    int number = scanner.nextInt(); 
    if (isDisarium(number)) 
      { System.out.println(number + " is a Disarium number."); } 
      else 
      { System.out.println(number + " is not a Disarium number."); } 
    scanner.close(); 
   } 
}

How the program works

  1. The countDigits method counts how many digits are in the number.
  2. The isDisarium method calculates the sum of each digit raised to the power of its position (starting from 1).
  3. The main method prompts the user for a number, checks if it’s a Disarium number, and outputs the result.

Pankaj Gupta Scholar

5 months ago

Program to perform Binary Search

Here’s a simple Java program to perform binary search on a sorted array of integers. Binary search works by repeatedly dividing the array in half and comparing the target value to the middle element, reducing the search interval by half each time.

import java.util.Scanner;

public class BinarySearch {

// Method to perform binary search
public static int binarySearch(int[] array, int target) {
int low = 0;
int high = array.length – 1;

// Continue searching while the range is valid
while (low <= high) {
// Calculate the middle index
int mid = low + (high – low) / 2;

// Check if the target is at the mid
if (array[mid] == target) {
return mid; // Target found, return the index
}

// If the target is greater, ignore the left half
if (array[mid] < target) {
low = mid + 1;
}
// If the target is smaller, ignore the right half
else {
high = mid – 1;
}
}

// Return -1 if the target is not found
return -1;
}

public static void main(String[] args) {
Scanner scanner = new Scanner(System.in);

// Input: Sorted array
System.out.print(“Enter the number of elements in the array: “);
int n = scanner.nextInt();
int[] array = new int[n];

System.out.println(“Enter ” + n + ” sorted elements: “);
for (int i = 0; i < n; i++) {
array[i] = scanner.nextInt();
}

// Input: Target element to search
System.out.print(“Enter the element to search for: “);
int target = scanner.nextInt();

// Perform binary search
int result = binarySearch(array, target);

// Output the result
if (result == -1) {
System.out.println(“Element not found.”);
} else {
System.out.println(“Element found at index: ” + result);
}

scanner.close();
}
}

 

Explanation of the program

    • Input: The user enters the number of elements, a sorted array, and the target element to search.
    • Binary Search:
      • The array is divided into two halves by calculating the middle element.
      • If the target is equal to the middle element, the search is successful.
      • If the target is smaller than the middle element, the search continues on the left half. Otherwise, it continues on the right half.
      • This process repeats until the target is found or the search space is exhausted.
    • Output: The program prints the index of the target element if found, or a message if it’s not found.