Validate Bitonic Array Max | Dataford Interview Questions

Given an array that increases and then decreases, first verify if it is valid, and then find the maximum value.

Asked in the Onsite Round 1 stage. Verification is done in O(N) and finding the maximum uses binary search O(log N). Reported follow-up: why a sequential linear search can be faster than binary search for small N on embedded memory and cache systems.

Function

def find_bitonic_max(nums):

Input

nums is a list of integers.

Output

Return the maximum value if nums is a valid bitonic array, otherwise return -1.

A valid bitonic array must strictly increase to a single peak and then strictly decrease. Arrays with fewer than 3 elements are invalid.

Constraints

1 <= nums.length <= 10^5
-10^9 <= nums[i] <= 10^9
A valid array must strictly increase then strictly decrease
Return -1 if the array is not valid

Function Signature

def find_bitonic_max(nums):

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