import java.util.Scanner;
 
public class Main {
 
	public static void main(String[] args) {
		Scanner s = new Scanner(System.in);
		long a=s.nextInt();
		long b=s.nextInt();
		if(a!=b){
		long max=Math.max(a, b);
		long min=Math.min(a, b);
		
		double c=Math.sqrt((double)max*max-min*min);
		System.out.println(c);
		}else{
			double c=Math.sqrt((double)a*a-b*b);
			System.out.println(c);
		}
	}
}