#include <iostream>
#include <string>
#include <vector>
#include <cmath>
#include <cstdio>
#include <climits>

using namespace std;

using ll = long long;

template <class T>
using grid = vector<vector<T>>;

#define REP(i,n) for(ll i=0;i<(ll)(n);i++)
#define REPD(i,n) for(ll i=n-1;i>=0;i--)
#define FOR(i,a,b) for(ll i=a;i<=(ll)(b);i++)
#define FORD(i,a,b) for(ll i=a-1;i>=(ll)(b);i--)

#define input(...) __VA_ARGS__; in(__VA_ARGS__)

void print() {
  std::cout << std::endl;
}

template <class Head, class... Tail>
void print(Head&& head, Tail&&... tail) {
  std::cout << head << " ";
  print(std::forward<Tail>(tail)...);
}

void in() { }

template <class Head, class... Tail>
void in(Head&& head, Tail&&... tail) {
  cin >> head;
  in(std::forward<Tail>(tail)...);
}

int Q, P;
double binary_search(double l, double r) {
  double center;
  REP(i, 100) {
    center = (l + r) / 2;
    if (center * center > P + Q * center * log2(center)) {
      r = center;
    } else {
      l = center;
    }
  }

  return center;
}

int main() {
  int input(p, q);
  Q = q; P = p;
  printf("%.10f\n", binary_search(0, LLONG_MAX));
}