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47 lines
1.0 KiB
Python
47 lines
1.0 KiB
Python
#!/usr/bin/env python3
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# -*- coding: utf-8 -*-
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# author: bt3gl
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def search(nums):
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# 1. find the smallest element in the rotate array
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# "left" will be used as index later
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left, right = 0, len(nums)
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while left < right:
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mid = (left + right) // 2
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if nums[mid] > nums[-1]:
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left = mid + 1
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else:
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right = mid
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# 2. write a binary search
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def bs(left, right, target):
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while left < right:
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mid = (left + right) // 2
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if nums[mid] == target:
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return mid
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elif nums[mid] > target:
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right = mid
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else:
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left = mid + 1
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return -1
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# 3. run for both sides
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response = bs(0, left, target)
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if response != -1:
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return response
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else:
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return bs(left, len(nums), target)
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