#include "bits/stdc++.h"
#define int long long
#define FOR(i, a, b) for (int i = (int)(a); i < (int)(b); i++)
#define rep(i, n) for (int i = 0; i < (int)(n); i++)
#define ALL(obj) begin(obj), end(obj)
#define MAX(x) *max_element(ALL(x))
#define MIN(x) *min_element(ALL(x))
#define LOWER_BOUND(A, key) distance(A.begin(), lower_bound(ALL(A), key))
#define UPPER_BOUND(A, key) distance(A.begin(), upper_bound(ALL(A), key))

using namespace std;
using ll      = long long;
const int MOD = (int)(1e9 + 7);
const int INF = (int)(1e13 + 7);

int ceil_(int a, int b) { return (a + (b - 1)) / b; }
int bpm(int x, unsigned int y) {
  if (x == 0) return 0;
  if (y == 0) return 1;
  int ans   = 1;
  int digit = (int)((log((double)y) / log((double)2) / 1 + 1));
  x %= MOD;
  for (unsigned int i = 0; i < digit; i++) {
    if (((y >> i) & 1u) == 1) ans = ans * x % MOD;
    x = x * x % MOD;
  }
  return ans;
}
template <class T>
void cumulative_sum(T container) {
  for (int i = 0; i < container.size() - 1; i++) container[i + 1] += container[i];
}

bool judge(double N, double P, double Q) {
  return P + Q * N * log2(N) >= N * N;
}

double bisect(double L, double R, double P, double Q) {
  double mid = (L + R) / 2;
  if (judge(mid, P, Q) and not judge(mid + 0.00001, P, Q)) {
    return mid;
  } else if (judge(mid, P, Q) and judge(mid + 0.00001, P, Q)) {
    return bisect(mid, R, P, Q);
  } else {
    return bisect(L, mid, P, Q);
  }
}

signed main() {
  double P, Q;
  cin >> P >> Q;
  cout << fixed << setprecision(10) << bisect(0, 1000000000000000000000.0, P, Q) << endl;
}