Problem: Find Peak Element

Statement

A peak element in an array is one that is strictly greater than both of its neighbors.

Given a $0$-indexed integer array nums, return the index of any peak element.

Note: Elements at the boundaries of the array are compared against $-\infty$. That is, nums[-1] and nums[n] are both treated as $-\infty$, where n is the length of nums. This means an element can be considered a peak if it only needs to be greater than its single existing neighbor at the edges. Additionally, no two adjacent elements in nums are equal. You must write an algorithm that runs in $O(\log n)$ time.

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