Twin primes

Twin primes
You are encouraged to solve this task according to the task description, using any language you may know.

Twin primes are pairs of natural numbers(P1 and P2) that satisfy the following:

1. P1 and P2 are primes
2. P1 + 2 = P2

Write a program that displays the number of twin primes that can be found under a user-inputted number.

Examples below:

Output:

> Search Size: 100
> 8 twin prime pairs.

> Search Size: 1000
> 35 twin prime pairs.

Java

BigInteger Implementation: <lang Java> import java.math.BigInteger; import java.util.Scanner;

public class twinPrimes {

   public static void main(String[] args) {
       Scanner input = new Scanner(System.in);
       System.out.println("Search Size: ");
       BigInteger max = input.nextBigInteger();
       int counter = 0;
       for(BigInteger x = new BigInteger("3"); x.compareTo(max) <= 0; x = x.add(BigInteger.ONE)){
           BigInteger sqrtNum = x.sqrt().add(BigInteger.ONE);
           if(x.add(BigInteger.TWO).compareTo(max) <= 0) {
               counter += findPrime(x.add(BigInteger.TWO), x.add(BigInteger.TWO).sqrt().add(BigInteger.ONE)) && findPrime(x, sqrtNum) ? 1 : 0;
           }
       }
       System.out.println(counter + " twin prime pairs.");
   }
   public static boolean findPrime(BigInteger x, BigInteger sqrtNum){
       for(BigInteger divisor = BigInteger.TWO; divisor.compareTo(sqrtNum) <= 0; divisor = divisor.add(BigInteger.ONE)){
           if(x.remainder(divisor).compareTo(BigInteger.ZERO) == 0){
               return false;
           }
       }
       return true;
   }

} </lang>

Output:

> Search Size: 
> 100
> 8 twin prime pairs.

> Search Size: 
> 1000
> 35 twin prime pairs.

REXX

<lang rexx></lang> out