import java.util.*;

public class Main {
	public static void main (String[] args) {
		Scanner sc = new Scanner(System.in);
		int p = sc.nextInt();
		int q = sc.nextInt();
		double left = 0;
		double right = Math.sqrt(Double.MAX_VALUE / 10);
		for (int i = 0; i < 100000; i++) {
		    double m = (left + right) / 2;
		    if (m * m <= p + q * m * Math.log(m) / Math.log(2)) {
		        left = m;
		    } else {
		        right = m;
		    }
		}
		System.out.println(java.math.BigDecimal.valueOf(left).toPlainString());
	}
}