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Find Peak Element

A peak element is an element that is strictly greater than its neighbors. Given an integer array nums, find a peak element and return its index.

You may assume nums[-1] = nums[n] = -infinity. If there are multiple peaks, return the index of any one.

Example:

Input:

1,2,3,1

Output:

Reasoning:

The input array is nums = [1, 2, 3, 1], and we need to find a peak element, which is an element strictly greater than its neighbors.
We compare each element with its neighbors:
- nums[0] = 1 is not greater than nums[1] = 2,
- nums[1] = 2 is not greater than nums[2] = 3,
- nums[2] = 3 is greater than both nums[1] = 2 and nums[3] = 1.
Since nums[2] = 3 is a peak element, we return its index, which is $2$ .
The final output is the index of the peak element, which is $\boxed{2}$ .

Constraints:

1 <= len(nums) <= 1000
-2^31 <= nums[i] <= 2^31 - 1
nums[i] != nums[i + 1] for all valid i

Editor

Python 3.13.1

Test Results

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