#include <stdio.h>
#include <math.h>

int main(void){
    int P, Q;
    double Nmax = 100000000000, Nmin = 1, mid;

    scanf("%d %d", &P, &Q);

    /*
    while(t > 0.00001){
        while(N * N <= P + Q * N * log2(N)) N += t;
        N -= t;
        t /= 10;
    }
    */
    while(Nmax - Nmin > 0.00001){
        mid = (Nmax + Nmin) / 2;
        if(mid * mid <= P + Q * mid * log2(mid)){
            Nmin = mid;
        }else{
            Nmax = mid;
        }
    }

    printf("%f", mid);
    
    return 0;
}