#include <bits/stdc++.h>
#include<iostream>
#include<iomanip>
#include<string>
#include<algorithm>
#include<vector>
#include<set>
#include<list>
#include<queue>
#include<math.h>
#include<bitset>
using ll = long long;
using namespace std;

int main()
{
    int a, b, h, o;
    double ans;
    cin >> a >> b;
    if (a != b){
        h = max(a, b);
        o = min(a, b);
    } else h = o = a;
    cout << fixed << setprecision(7);
    if ((h*h - o*o) > 0) cout << sqrt(h*h - o*o) << endl;
    else cout << sqrt(h*h + o*o) << endl;
}