#include <iostream>
#include <cmath>
#include <algorithm>
using namespace std;

int main(){
    double a,b;
    cin>>a>>b;
    if(a<b)swap(a,b);
    double c1=sqrt(pow(a,2)-pow(b,2));
    double c2=sqrt(pow(a,2)+pow(b,2));
    cout.precision(10);
    if(a==b)cout<<c2<<endl;
    else cout<<min(c1,c2)<<endl;
    return 0;
}