Question
There is an integer array nums sorted in ascending order (with distinct values).
Prior to being passed to your function, nums is possibly rotated at an unknown pivot index k (1 <= k < nums.length) such that the resulting array is [nums[k], nums[k+1], ..., nums[n-1], nums[0], nums[1], ..., nums[k-1]] (0-indexed). For example, [0,1,2,4,5,6,7] might be rotated at pivot index 3 and become [4,5,6,7,0,1,2].
Given the array nums after the possible rotation and an integer target, return the index of target if it is in nums, or -1 if it is not in nums.
You must write an algorithm with O(log n) runtime complexity.
Example 1:
Input: nums = [4,5,6,7,0,1,2], target = 0 Output: 4
Example 2:
Input: nums = [4,5,6,7,0,1,2], target = 3 Output: -1
Example 3:
Input: nums = [1], target = 0 Output: -1
Constraints:
1 <= nums.length <= 5000-104 <= nums[i] <= 104- All values of
numsare unique. numsis an ascending array that is possibly rotated.-104 <= target <= 104
Python Solution
class Solution:
def search(self, nums: List[int], target: int) -> int:
if nums==None or len(nums)==0:
return -1
l = 0
r = len(nums)-1
while l<r:
m = l +(r-l)//2
if nums[m]>nums[r]:
l = m+1
else:
r=m
start = l
l = 0
r = len(nums)-1
if target>=nums[start] and target<=nums[r]:
l = start
else:
r=start-1
while(l<=r):
m = l+(r-l)//2
if nums[m]==target:
return m
elif target<nums[m]:
r=m-1
else :
l=m+1
return -1