## DEV Community

Abhishek Chaudhary

Posted on

# 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. 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: 2
Explanation: 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: 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.

Constraints:

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

SOLUTION:

``````class Solution:
def findPeakElement(self, nums: List[int]) -> int:
n = len(nums)
for i in range(n):
left = nums[i] > nums[i - 1] if i > 0 else True
right = nums[i] > nums[i + 1] if i < n - 1 else True
if left and right:
return i
``````