from math import log2
p, q = map(int, input().split())
def bsearch(mn, mx, func):
    #func(i)=False を満たす最大のi (mn<=i<mx)
    idx = (mx + mn)/2
    for _ in range(10**5):
        if func(idx):
            idx, mx = (idx + mn)/2, idx
            continue
        idx, mn = (idx + mx)/2, idx
    return idx

def f(x):
    return x**2-(p+x*log2(x)*q) > 0

#print(f(3))
#print(f(4))
print(bsearch(1, 10**18, f))