#include <iostream>
#include <algorithm>
#include <map>
#include <set>
#include <queue>
#include <stack>
#include <numeric>
#include <bitset>
#include <cmath>

static const int MOD = 1000000007;
using ll = long long;
using u32 = unsigned;
using u64 = unsigned long long;
using namespace std;

template<class T> constexpr T INF = ::numeric_limits<T>::max()/32*15+208;

int main() {
    double p, q;
    cin >> p >> q;
    double ok = 0, ng = 1e15;
    for (int i = 0; i < 100; ++i) {
        double mid = (ok+ng)/2;
        if(mid*mid <= p+q*mid*log2(mid)) ok = mid;
        else ng = mid;
    }
    printf("%.10lf\n", ok);
    return 0;
}