#include<iostream>
#include<cmath>
#include<iomanip>
using namespace std;
double P,Q;
main()
{
	cin>>P>>Q;
	double L=1,R=1e11;
	for(int tm=0;tm<100;tm++)
	{
		double M=(L+R)/2;
		if(M*M<P+Q*M*log2(M)+1e-10)L=M;
		else R=M;
	}
	cout<<fixed<<setprecision(16)<<L<<endl;
}