Python 解LeetCode：33. Search in Rotated Sorted Array
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题目描述：在一个旋转数组中查找给定的值，其中旋转数组中不含重复值；
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思路：
- 第一遍二分遍历，找到数组中最小值的索引；
- 第二遍分别对最小值左右两边的数组进行二分查找；
class Solution(object):
def find_min(self, nums):
if not nums:
return -1
left, right = 0, len(nums) - 1
while nums[left] > nums[right]:
if right - left == 1:
return right
mid = (left + right) / 2
if nums[left] <= nums[mid]:
left = mid
if nums[right] >= nums[mid]:
right = mid
return 0
def search(self, nums, target):
"""
:type nums: List[int]
:type target: int
:rtype: int
"""
if not nums:
return -1
min_index = self.find_min(nums)
if nums[min_index] == target:
return min_index
elif nums[min_index] > target:
return -1
else:
left = self.search_t(nums, 0, min_index, target)
if left >= 0:
return left
right = self.search_t(nums, min_index, len(nums)-1, target)
if right >= 0:
return right
return -1
def search_t(self, nums, left, right, target):
while left <= right:
mid = (left + right) / 2
if nums[mid] == target:
return mid
elif nums[mid] < target:
left = mid + 1
else:
right = mid - 1
return -1
