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

int main(){
  int a, b; cin >> a >> b;
  double ans = 0;
  if(a==b) ans = sqrt(a*a+b*b);
  else ans = sqrt(max(a,b)*max(a,b)-min(a,b)*min(a,b));
  printf("%.10f\n",ans);
  return 0;
}