def pow(x, n):
r = 1.0
if n < 0:
x = 1.0/x
n = -n
for a, b in izip(square(x), int2digits(n, 2)):
if b:
r *= a
return r
def isPalindrome(x):
if x < 0:
return False
return x == digits2int_b(int2digits(x))
def isPalindrome(x):
if x < 0:
return False
return x == digits2int_b(int2digits(x))
def reverse(x):
n = sign(x) * digits2int_b(int2digits(abs(x)))
return overflow32(n, 0, 0)
