import math

def is_ok(N):
	return N**2<=P+Q*N*math.log2(N)

P,Q=map(int,input().split())
ok=1
ng=10**18
while ng-ok>10**(-5):
	m=(ok+ng)/2
	if is_ok(m):
		ok=m
	else:
		ng=m
print(ok)