Implement pow(x, n), which calculates x raised to the power n (xn).
Example 1:
Input: 2.00000, 10
Output: 1024.00000
Example 2:
Input: 2.10000, 3
Output: 9.26100
Example 3:
python:分治思想
class Solution(object):
def myPow(self, x, n):
"""
:type x: float
:type n: int
:rtype: float
"""
if n==0:
return 1
if n<0:
return 1.0/self.myPow(x,-n)
if n%2==0:
return self.myPow(x*x,n/2)
else:
return x*self.myPow(x*x,(n-1)/2)