**6.29 (Twin primes) Twin primes are a pair of prime numbers that differ by 2. For example,
3 and 5 are twin primes, 5 and 7 are twin primes, and 11 and 13 are twin primes.
Write a program to find all twin primes less than 1,000. Display the output as follows:
(3, 5)
(5, 7)
...
(3, 5)
(5, 7)
...
public class ProgrammingExercise6_29 { public static void main(String[] args) { // TODO Auto-generated method stub for (int i = 2; i < 1000; i++) { if (isPrime(i)&&isPrime(i+2)) { System.out.printf("(%d, %d)\n", i, i+2); } } } /** Check whether number is prime */ public static boolean isPrime(int number) { for (int divisor = 2; divisor <= number / 2; divisor++) { if (number % divisor == 0) { // If true, number is not prime return false; // number is not a prime } } return true; // number is prime } }
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