#include <bits/stdc++.h>
using namespace std;
 
#define lli long long int
#define REP(i,s,n) for(int i=s;i<n;i++)
#define NUM 2520
#define INF (1LL<<50)
#define DEBUG 0
#define mp(a,b) make_pair(a,b)
#define SORT(V) sort(V.begin(),V.end())
#define PI (3.141592653589794)
#define TO_STRING(VariableName) # VariableName
#define LOG(x) if(DEBUG)cout<<TO_STRING(x)<<"="<<x<<" "<<endl;
#define LOG2(x,y) if(DEBUG)cout<<TO_STRING(x)<<"="<<x<<" "<<TO_STRING(y)<<"="<<y<<endl;
#define LOG3(x,y,z) if(DEBUG)cout<<TO_STRING(x)<<"="<<x<<" "<<TO_STRING(y)<<"="<<y<<" "<<TO_STRING(z)<<"="<<z<<endl;
#define LOG4(w,x,y,z) if(DEBUG)cout<<TO_STRING(w)<<"="<<w<<" "<<TO_STRING(x)<<"="<<x<<" "<<TO_STRING(y)<<"="<<y<<" "<<TO_STRING(z)<<"="<<z<<endl;
 
template<class T>bool chmax(T & a, const T & b) { if (a < b) { a = b; return 1; } return 0; }
template<class T>bool chmin(T& a, const T& b) { if (b < a) { a = b; return 1; } return 0; }
 
double calc(lli p,lli q,double n){
	return p+n*q*log2(n);
}

int main(){

	lli P,Q;
	cin>>P>>Q;

	double large = 1e18,small = 1;

	lli cnt=0;
	while(cnt<100000){
		double middle = (large+small)/2.0;
		double t = middle*middle;
		double l = calc(P,Q,middle);
		LOG3(middle,t,l);
		if(t>l)large=middle;
		else small = middle;
		cnt++;
	}
	cout<<setprecision(20);
	cout<<small<<endl;

    return 0;
}