import java.util.Scanner;

class Main{
    public static void main(String[] args){
        Scanner sc=new Scanner(System.in);
        double a=sc.nextDouble(),b=sc.nextDouble(),c,d;
        sc.close();
        c=a*a-b*b;
        d=b*b-a*a;
        System.out.print(a!=b?Math.sqrt(c)<Math.sqrt(d)?Math.sqrt(Math.abs(c)):Math.sqrt(Math.abs(d)):Math.sqrt(a*b+a*b));
    }
}