Solution.java

import static java.lang.System.in;


class Prime {
    void checkPrime(int... numbers) {
        for (int num : numbers) {
            if (isPrime(num)) {
                System.out.print(num + " ");
            }
        }
        System.out.println();
    }
    
    boolean isPrime(int n) {
        if (n < 2) {
            return false;
        } else if (n == 2) {     // account for even numbers now, so that we can do i+=2 in loop below
            return true;
        } else if (n % 2 == 0) { // account for even numbers now, so that we can do i+=2 in loop below
            return false;
        }
        int sqrt = (int) Math.sqrt(n);
        for (int i = 3; i <= sqrt; i += 2) { // skips even numbers for faster results
            if (n % i == 0) {
                return false;
            }
        }
        return true;
    }
}