p,q=map(int,input().split())

l=1
r=10**12

import math

def takawin(x):
    if abs(x-1)<10**-6:
        return True
    elif (x**2-p)/x<q*math.log2(x):
        return True
    else: return False

for _ in range(10000):
    mid=(r+l)/2
    if takawin(mid):
        l=mid
    else:
        r=mid

print("{:.8f}".format(r))