import java.util.Scanner;

public class No419 {
	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		double a = sc.nextDouble();
		double b = sc.nextDouble();
		
		if(a == b) {
			System.out.println(Math.sqrt(Math.pow(a, 2) * 2));
		}else {
		System.out.println(Math.sqrt(Math.pow(Math.max(a, b), 2) - Math.pow(Math.min(a, b), 2)));
		}
	}
}