#include <bits/stdc++.h>
using namespace std;
typedef long long int ll;
typedef pair<ll, ll> P;
typedef vector<ll> VI;
typedef vector<VI> VVI;
const ll MOD = 1000000007;
const ll INF = 2147483647;
const ll LINF = 9223372036854775807;
#define REP(i, n) for (int i = 0; i < n; i++)
#define ALL(v) v.begin(), v.end()

int main() {
	ll p, q; cin >> p >> q;
	long double ok=1, ng=LINF;
	while(ng-ok>0.00000001){
		long double s=ok+(ng-ok)/2;
		if(s*s<p+q*s*log2(s))
			ok=s;
		else
			ng=s;
	}
	cout << setprecision(10) << ok << endl;
	return 0;
}