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

int main()
{
	long long P, Q;
	cin >> P >> Q;

	long double EPS = 0.0000001;
	long double l = 0;
	long double r = 100000000000;
	while( r - l > EPS ) {
		long double N = ( l + r ) / 2;
		if( N * N <= P + Q * N * log2( N ) ) l = N;
		else r = N;
	}
	long double ans = l;

	cout << fixed << setprecision(12) << ans << endl;
}