How to check a number is Prime or Composite in Java and C++ Coding

 Check Prime Number in Java and C++ easily

We will code a program which will take a input value and tell us whether it is a prime number or a composite number.

Prime Numbers in Blue Box

Here is a C++ Code for checking a prime number.

#include <bits/stdc++.h>

#define ed		"\n"

using namespace std;
int main()
{
	unsigned long long int number;
	bool isPrime = true;
	cin >> number;

	if (number == 0 || number == 1)
	{
		cout << number << " is neither Prime nor composite "<<ed;
		return 0;
	}
	for (unsigned long long int i = 2; i*i < number; ++i)
	 {
	 	if (number%i == 0)
	 	{
	 		isPrime = false;
	 		break;
	 	}
	 } 
	 if (isPrime)
	 {
	 	cout << number << " is a Prime number" << ed;
	 }
	 else
	 {
	 	cout << number << " is a composite number" << ed;
	 }
    return 0;
}
// Check it for 922337203685477537 
 

And here is the equivalent code in Java

package proj01;

import java.util.Scanner;

public class TestJava
{
    public static void main(String[] args) {

    Scanner sc = new Scanner(System.in);
        
    System.out.print("Enter a number:");
    long number = sc.nextLong();
	boolean isPrime = true;
      
	if (number == 0 || number == 1)
	{
		System.out.println(number + " is neither Prime nor composite.");
        System.exit(0);
	}
	for (long i = 2; i*i < number; ++i)
	 {
	 	if (number%i == 0)
	 	{
	 		isPrime = false;
	 		break;
	 	}
	 } 
	 if (isPrime)
	 {
        System.out.println(number + " is a Prime Number");
	 }
	 else
	 {
        System.out.println(number + " is a composite Number");
	 }
	// hljs.initHighlightingOnLoad();
    }
}

// 922337203685477537