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Find Peak Element

Problem statement​

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. If the array contains multiple peaks, return the index to any of the peaks.

You may imagine that nums[-1] = nums[n] = -∞.

You must write an algorithm that runs in O(log n) time.

Example 1:

Input: nums = [1,2,3,1]Output: 2Explanation: 3 is a peak element and your function should return the index number 2.

Example 2:

Input: nums = [1,2,1,3,5,6,4]Output: 5Explanation: Your function can return either index number 1 where the peak element is 2, or index number 5 where the peak element is 6.

Constraints:

  • 1 <= nums.length <= 1000
  • -231 <= nums[i] <= 231 - 1
  • nums[i] != nums[i + 1] for all valid i.

My solution​

/**
 * @param {number[]} nums
 * @return {number}
 */
var findPeakElement = function(nums) {
    const result = [];
    if (nums.length === 1) {
        return 0;
    }
    for (let i = 0; i < nums.length; i++) {
        const curr = nums[i];
        const left = nums[i - 1] || Number.MIN_SAFE_INTEGER;
        const right = nums[i + 1] || Number.MIN_SAFE_INTEGER;
        
        // console.log(curr, left, right)
        
        if (curr > left && curr > right) {
            result.push(i);
        } else {
            
        }
    }
    
    return result.pop()
};