#include<iostream>
#include<iomanip>
#include<cmath>
signed main(){
  double p,q;
  std::cin>>p>>q;
  double loweq = 1.0;
  double high = 1e8;
  int loop = 1000;
  while(loop--){
    double n = (loweq+high)/2.0;
    if(n*n<p+q*n*std::log2(n))loweq = n;
    else high = n;
  }
  std::cout<<std::fixed<<std::setprecision(10)<<loweq<<std::endl;
}