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Define a class to accept 10 integers and arrange them in descending order using bubble sort technique print the original array and sorted array.​

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Here’s a Java program that defines a class to accept 10 integers and arranges them in descending order using the bubble sort technique. It then prints the original array and the sorted array:

import java.util.Scanner;

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

        // Accept 10 integers
        int[] array = new int[10];
        System.out.println("Enter 10 integers:");

        for (int i = 0; i < array.length; i++) {
            System.out.print("Enter integer " + (i + 1) + ": ");
            array[i] = scanner.nextInt();
        }

        // Perform bubble sort in descending order
        for (int i = 0; i < array.length - 1; i++) {
            for (int j = 0; j < array.length - 1 - i; j++) {
                if (array[j] < array[j + 1]) {
                    // Swap elements if they are in the wrong order
                    int temp = array[j];
                    array[j] = array[j + 1];
                    array[j + 1] = temp;
                }
            }
        }

        // Print the original array
        System.out.print("\nOriginal Array: ");
        for (int num : array) {
            System.out.print(num + " ");
        }

        // Print the sorted array
        System.out.print("\nSorted Array (Descending): ");
        for (int num : array) {
            System.out.print(num + " ");
        }

        scanner.close();
    }
}

Explanation:

1. Import Statements:

   • import java.util.Scanner;: This line imports the Scanner class from the java.util package, which is used for taking input from the user.

2. Class Declaration:

   • public class BubbleSortDescending {: This line declares a class named BubbleSortDescending.

3. Main Method:

   • public static void main(String[] args) {: This is the entry point of the program. The main method is where the program execution starts.

4. Array Initialization:

   • int[] array = new int[10];: An array named array is declared to store 10 integers.

5. Accepting User Input:

   • A for loop is used to accept 10 integers from the user and store them in the array.

6. Bubble Sort Algorithm:

   • Two nested for loops implement the bubble sort algorithm.
   • The outer loop (i) controls the number of iterations, and the inner loop (j) compares adjacent elements and swaps them if they are in the wrong order.
   • The comparison is done in descending order (array[j] < array[j + 1]), and the elements are swapped if the condition is true.

7. Printing the Original and Sorted Arrays:

   • The program prints the original array and the sorted array (in descending order) after the bubble sort.

8. Closing Scanner:

   • scanner.close();: This line closes the Scanner object to prevent resource leaks.

This program demonstrates the use of arrays, user input, and the bubble sort algorithm to arrange elements in descending order.

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Define a class to accept 10 character and arrange them in ascending order using bubble sort technique print the original array and sorted array.

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Here’s a Java program that defines a class to accept 10 characters and arranges them in ascending order using the bubble sort technique. It then prints the original array and the sorted array:

import java.util.Scanner;

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

        // Accept 10 characters
        char[] charArray = new char[10];
        System.out.println("Enter 10 characters:");

        for (int i = 0; i < 10; i++) {
            System.out.print("Enter character " + (i + 1) + ": ");
            charArray[i] = scanner.next().charAt(0);
        }

        // Perform bubble sort
        for (int i = 0; i < 9; i++) {
            for (int j = 0; j < 9 - i; j++) {
                if (charArray[j] > charArray[j + 1]) {
                    // Swap characters
                    char temp = charArray[j];
                    charArray[j] = charArray[j + 1];
                    charArray[j + 1] = temp;
                }
            }
        }

        // Print original array
        System.out.print("\nOriginal array: ");
        for (char ch : charArray) {
            System.out.print(ch + " ");
        }

        // Print sorted array
        System.out.print("\nSorted array: ");
        for (char ch : charArray) {
            System.out.print(ch + " ");
        }

        scanner.close();
    }
}

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Java Program to Count the Number of Alphabets, Numbers, and Special Characters in a Given String.

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Below are two Java programs. The first one calculates the number of alphabets, numbers, and special characters in a given string. The second program takes input from the user:

import java.util.Scanner;

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

        System.out.print("Enter a string: ");
        String inputString = scanner.nextLine();

        int alphabetCount = 0;
        int numberCount = 0;
        int specialCharCount = 0;

        for (char ch : inputString.toCharArray()) {
            if (Character.isLetter(ch)) {
                alphabetCount++;
            } else if (Character.isDigit(ch)) {
                numberCount++;
            } else {
                specialCharCount++;
            }
        }

        System.out.println("Alphabets: " + alphabetCount);
        System.out.println("Numbers: " + numberCount);
        System.out.println("Special Characters: " + specialCharCount);

        scanner.close();
    }
}

Explanation:

This program is similar to the first one, but it takes input from the user.

1. Scanner Initialization:

Scanner scanner = new Scanner(System.in);

1. Initializes a Scanner object to take user input.
2. User Input:

System.out.print("Enter a string: ");
String inputString = scanner.nextLine();

1. Prompts the user to enter a string, and reads the input.
2. Character Counting (Same as Program 1): The remaining part of the code is the same as Program 1, where it counts the number of alphabets, numbers, and special characters in the input string.
3. Scanner Closing:

scanner.close();

• Closes the Scanner object to prevent resource leaks.

These programs demonstrate how to count the number of alphabets, numbers, and special characters in a given string, and the second one allows user input.

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Write a java program which creates class Student (Rollno, Name,- Number of subjects,Marks of each subject)(Number of subjects varies for each student) Write a parameterized constructor which initializes roll no, name & Number of subjects and create the array of marks dynamically. Display the details of all students with percentage and class obtained.

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Below is a Java program that fulfills the given requirements. The program defines a Student class with a parameterized constructor, dynamically creates an array of marks, and displays details including percentage and class obtained for each student.

import java.util.Scanner;

class Student {
    private int rollNo;
    private String name;
    private int numSubjects;
    private int[] marks;

    // Parameterized constructor to initialize roll no, name, and number of subjects
    public Student(int rollNo, String name, int numSubjects) {
        this.rollNo = rollNo;
        this.name = name;
        this.numSubjects = numSubjects;

        // Dynamically create an array of marks based on the number of subjects
        this.marks = new int[numSubjects];
    }

    // Method to input marks for each subject
    public void inputMarks(Scanner scanner) {
        System.out.println("Enter marks for each subject for student " + rollNo + ":");
        for (int i = 0; i < numSubjects; i++) {
            System.out.print("Enter marks for Subject " + (i + 1) + ": ");
            marks[i] = scanner.nextInt();
        }
    }

    // Method to calculate percentage
    public double calculatePercentage() {
        int totalMarks = 0;
        for (int mark : marks) {
            totalMarks += mark;
        }

        return (double) totalMarks / numSubjects;
    }

    // Method to determine class obtained based on percentage
    public String determineClass() {
        double percentage = calculatePercentage();

        if (percentage >= 80) {
            return "Distinction";
        } else if (percentage >= 60) {
            return "First Class";
        } else if (percentage >= 40) {
            return "Pass Class";
        } else {
            return "Fail";
        }
    }

    // Method to display student details
    public void displayDetails() {
        System.out.println("\nStudent Details:");
        System.out.println("Roll No: " + rollNo);
        System.out.println("Name: " + name);
        System.out.println("Number of Subjects: " + numSubjects);
        System.out.println("Marks: " + java.util.Arrays.toString(marks));
        System.out.println("Percentage: " + calculatePercentage() + "%");
        System.out.println("Class Obtained: " + determineClass());
    }
}

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

        // Input the number of students
        System.out.print("Enter the number of students: ");
        int numStudents = scanner.nextInt();

        // Create an array of Student objects
        Student[] students = new Student[numStudents];

        // Input details for each student
        for (int i = 0; i < numStudents; i++) {
            System.out.println("\nEnter details for Student " + (i + 1) + ":");
            System.out.print("Enter Roll No: ");
            int rollNo = scanner.nextInt();
            System.out.print("Enter Name: ");
            String name = scanner.next();
            System.out.print("Enter Number of Subjects: ");
            int numSubjects = scanner.nextInt();

            // Create a Student object with input details
            students[i] = new Student(rollNo, name, numSubjects);

            // Input marks for each subject
            students[i].inputMarks(scanner);
        }

        // Display details for each student
        for (Student student : students) {
            student.displayDetails();
        }

        scanner.close();
    }
}

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Explanation:

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• The program defines a Student class with private instance variables (rollNo, name, numSubjects, marks).
• The constructor Student(int rollNo, String name, int numSubjects) initializes the basic details and dynamically creates an array for marks based on the number of subjects.
• The program then takes input for the number of students, creates an array of Student objects, and inputs details for each student.
• Each student’s details, including percentage and class obtained, are then displayed. The class obtained is determined based on the percentage.
• The program uses methods to organize functionality and keep the code modular and readable.

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