02_FindThePeakElement.py

# Question link https://leetcode.com/problems/find-peak-element/description/?envType=study-plan-v2&envId=top-interview-150

class Solution:
    def findPeakElement(self, nums: List[int]) -> int:
        n = len(nums)
        if (n==1): #For only one elements
            return 0
        if (nums[0] > nums[1]) : #For peak at Oth index
            return 0
        if (nums[n-1] > nums[n-2]): #For peak in n-1th index
            return n-1

        low , high = 1 , n - 2
        while(low <= high):
            mid = (low + high) // 2

            if ((nums[mid] > nums[mid - 1]) and (nums[mid] > nums[mid+1])):
                return mid # the peak is in the mid
            # If peak is in right half
            elif (nums[mid] > nums[mid - 1]):
                low = mid + 1
            else:
                # peak is in left half
                high = mid - 1
        return -1