leetcode

Find Peak Element

Find Peak Element

Binary Search Version - 36ms

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class Solution:
    def findPeakElement(self, nums):
        """
        :type nums: List[int]
        :rtype: int
        """
        left = 0
        right = len(nums) - 1
        while left < right - 1:
            mid = (left + right) // 2
            if nums[mid - 1] < nums[mid] and nums[mid] > nums[mid + 1]:
                return mid
            if nums[mid] < nums[mid + 1]:
                left = mid + 1
            else:
                right = mid - 1
        return left if nums[left] >= nums[right] else right

test code

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In [7]: nums = [1,2,3,1]
In [17]: s = Solution(); t = s.findPeakElement(nums)
In [18]: t
Out[18]: 2
In [19]: nums = [1,2,1,3,5,6,4]
In [20]: s = Solution(); t = s.findPeakElement(nums)
In [21]: t
Out[21]: 5

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