Java Online Compiler
Example: Prime Number Checker in Java
C
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Java
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Main.java
STDIN
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// Prime Number Checker import java.util.Scanner; // Main class containing the entry point of the program public class Main { public static void main(String[] args) { // Step 1: Create a Scanner object to read user input Scanner scanner = new Scanner(System.in); // Step 2: Prompt the user to enter a number System.out.print("Enter a number: "); int number = scanner.nextInt(); // Step 3: Initialize a boolean flag to track primality boolean isPrime = true; // Step 4: Handle special cases for numbers less than or equal to 1 if (number <= 1) { isPrime = false; } else { // Step 5: Iterate from 2 up to the square root of the number // If any number in this range divides 'number' evenly, it's not prime for (int i = 2; i * i <= number; i++) { if (number % i == 0) { isPrime = false; break; // No need to check further, it's not prime } } } // Step 6: Print the result based on the isPrime flag if (isPrime) { System.out.println(number + " is a prime number."); } else { System.out.println(number + " is not a prime number."); } // Step 7: Close the scanner to prevent resource leaks scanner.close(); } }
Output
Clear
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