#include<bits/stdc++.h>
using namespace std;
using Int = long long;

template<typename T1,typename T2> inline void chmin(T1 &a,T2 b){if(a>b) a=b;}
template<typename T1,typename T2> inline void chmax(T1 &a,T2 b){if(a<b) a=b;}


struct Precision{
  Precision(){
    cout<<fixed<<setprecision(12);
  }
}precision_beet;

//INSERT ABOVE HERE
signed main(){
  double a,b;
  cin>>a>>b;
  double c=sqrt(a*a+b*b);
  if(a>b) swap(a,b);
  if(a!=b) chmin(c,sqrt(b*b-a*a));
  cout<<c<<endl;
  return 0;
}