#include<bits/stdc++.h>

int main(){
    using namespace std;
    long double P, Q;
    cin >> P >> Q;
    const auto& check = [&P, &Q](long double N) -> bool{
        return P + Q * log2(N) * N <= N * N;
    };
    long double L{1}, R{1000000000000};
    for(unsigned long _{0}; _ < 60; ++_){
        long double M = sqrt(L * R);
        (check(M) ? R : L) = M;
    }
    printf("%.12Lf\n", R);
    return 0;
}