Published May 15, 2022
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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.
Input: nums = [1,2,3,1]
Output: 2
Explanation: 3 is a peak element and your function should return the index number 2.
Input: nums = [1,2,1,3,5,6,4]
Output: 5
Explanation: Your function can return either index number 1 where the peak element is 2, or index number 5 where the peak element is 6.
1 <= nums.length <= 1000-2^31 <= nums[i] <= 2^31 - 1nums[i] != nums[i + 1] for all valid i.function findPeakElement(nums: number[]): number {
let l: number = 0, r = nums.length - 1;
while(l < r){
let mid: number = Math.floor((l + r)/2);
// we are in decreasing line
if(nums[mid] > nums[mid + 1]){
r = mid
} else {
l = mid + 1
}
}
return l
};