Problem statement

https://binarysearch.com/problems/Strictly-Increasing-or-Strictly-Decreasing/

Solution

Almost the same as Leetcode 0896 Monotonic Array.

Complexity

It is O(n) for time and space.

Code

class Solution:
    def solve(self, A):
        inc = dec = True

        for i in range(len(A) - 1):
            if A[i] >= A[i+1]: inc = False
            if A[i] <= A[i+1]: dec = False

        return inc or dec