Prime Number in Java

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Q. Write a Java program to check Prime Number or Not

 import java.util.Scanner;

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

        // Ask the user to enter a number
        System.out.print("Enter a number: ");
        int number = scanner.nextInt();

        boolean isPrime = true;

        // 0 and 1 are not prime numbers
        if (number <= 1) {
            isPrime = false;
        } else {
            // Check from 2 to sqrt(number)
            for (int i = 2; i <= Math.sqrt(number); i++) {
                if (number % i == 0) {
                    isPrime = false;
                    break;
                }
            }
        }

        // Display result
        if (isPrime) {
            System.out.println(number + " is a Prime number.");
        } else {
            System.out.println(number + " is NOT a Prime number.");
        }

        scanner.close();
    }
}
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Q. Write an algorithm to check Prime Number or Not

1. Start
2. Read an integer and store it in number
3. If number <= 1, set isPrime = false
4. Else, repeat from i = 2 to √number:
    a. If number % i == 0, set isPrime = false and break the loop
5. If isPrime == true, print "Prime number"
6. Else, print "Not a Prime number"
7. End
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