from math import *

def binary_search():
    l, r = 1, 10**18
    
    while r-l>=1e-6:
        m = (l+r)/2
        
        if m**2<=P+Q*m*log(m, 2):
            l = m
        else:
            r = m

    return l

P, Q = map(int, input().split())
print(binary_search())