Input Format

A single line containing an integer,  (the number to be checked).

Constraints

•  contains at most  digits.

Output Format

If  is a prime number, print prime; otherwise, print not prime.

# Java Primality test problem solution | HackerRank

import java.io.*;
import java.util.*;
import java.text.*;
import java.math.*;
import java.util.regex.*;

public class Solution {

public static void main(String[] args) {
Scanner in = new Scanner(System.in);
BigInteger n = in.nextBigInteger();
in.close();
if(n.isProbablePrime(1)){
System.out.println("prime");
}
else{
System.out.println("not prime");
}

}
}

## Second solution

import java.math.*;

public class BigIntegerDemo {

public static void main(String[] args) {

// create 2 BigInteger objects
BigInteger n1,n2;

// create 3 Boolean objects
Boolean b1, b2, b3;

// assign values to n1, n2
n1 = new BigInteger("7");
n2 = new BigInteger("9");

// perform isProbablePrime on n1, n2
b1 = n1.isProbablePrime(1);
b2 = n2.isProbablePrime(1);
b3 = n2.isProbablePrime(-1);

// check if n1 is prime or not if certainity =1
if(b1)
System.out.println(n1 + " is prime with certainity 1" );
else
System.out.println(n1 + " is not prime with certainity 1" );

// check if n2 is prime or not if certainity =1
if(b2)
System.out.println(n2 + " is prime with certainity 1" );
else
System.out.println(n2 + " is not prime with certainity 1" );

// check if n2 is prime or not if certainity =-1
if(b3)
System.out.println(n2 + " is prime with certainity -1");
else
System.out.println(n2 + " is not prime with certainity -1" );
}
}