public class WhileLoopExample {
    public static void main(String[] args) {
        double n = 20;
        
        double guess = n / 2;
        while (guess * guess < n - 0.0001 || guess * guess > n + 0.0001) {
            guess = (n / guess + guess) / 2;
            System.out.println(guess + " squared is " + guess * guess
                    + " and n / guess is "
                    + n / guess);
        }
    }
}