using System;
using System.Collections.Generic;
using System.Linq;

//YukiCoder419 直角三角形
//http://yukicoder.me/problems/no/419
class Program
{
    static string InputPattern = "InputX";

    static List<string> GetInputList()
    {
        var WillReturn = new List<string>();

        if (InputPattern == "Input1") {
            WillReturn.Add("4 5");
            //3.0000000000
        }
        else if (InputPattern == "Input2") {
            WillReturn.Add("5 3");
            //4.0000000000
        }
        else if (InputPattern == "Input3") {
            WillReturn.Add("3 4");
            //2.6457513111
        }
        else {
            string wkStr;
            while ((wkStr = Console.ReadLine()) != null) WillReturn.Add(wkStr);
        }
        return WillReturn;
    }

    static void Main()
    {
        List<string> InputList = GetInputList();
        double[] wkArr = InputList[0].Split(' ').Select(X => double.Parse(X)).ToArray();

        double C = wkArr.Max();
        double B = wkArr.Min();

        double A = Math.Sqrt(C * C - B * B);

        Console.WriteLine(A);
    }
}