#include <iostream>
#include <iomanip>
#include <cmath>

using ldouble = long double;

void solve() {
    ldouble p, q;
    std::cin >> p >> q;

    ldouble ok = 1, ng = 1e20;
    for (int i = 0; i < 200; ++i) {
        ldouble n = (ok + ng) / 2;
        if (n * n - n * q * std::log2(n) - p <= 0) {
            ok = n;
        } else {
            ng = n;
        }
    }

    std::cout << std::fixed << std::setprecision(10)
              << ok << std::endl;
}

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

    solve();

    return 0;
}