#include <bits/stdc++.h>
#define rep(i,n) for (int i = 0; i < n; ++i)
#define ALL(c) (c).begin(), (c).end()
#define SUM(x) std::accumulate(ALL(x), 0LL)
#define MIN(v) *std::min_element(v.begin(), v.end())
#define MAX(v) *std::max_element(v.begin(), v.end())
#define EXIST(v, x) (std::find(v.begin(), v.end(), x) != v.end())
using namespace std;

using ll = long long;

template<class T> inline bool chmax(T& a, T b) { if (a < b) { a = b; return true; } return false; }
template<class T> inline bool chmin(T& a, T b) { if (a > b) { a = b; return true; } return false; }
const int INF = 1e9;
const long long INFL = 1LL<<60;

bool taka_win(ll p, ll q, double n) {
  bool ret = double(n * n) <= double(p + q * n * log2(n));
  return ret;
}

int main() {
  cin.tie(0);
  ios::sync_with_stdio(false);

  ll p, q;
  cin >> p >> q;

  double lb = 1;
  double ub = INFL;

  rep(i, 100000) {
    double mid = lb + (ub - lb) / 2;
    if (taka_win(p, q, mid)) lb = mid;
    else ub = mid;
  }

  printf("%.6f\n", lb);

  return 0;
}