Pow(x,n)

class Solution:

    def myPow(self, x, n):

        """

        :type x: float

        :type n: int

        :rtype: float

        """

        is_negative = False

        if n < 0:

            is_negative = True

            n = -1 * n

        result = 1

        while n > 0: 

            if n%2 != 0:

                result = result * x

            x = x * x

            n = int(n/2)

        return  1/result if is_negative  else result