1878 Check If Array Is Sorted And Rotated

Check if Array Is Sorted and Rotated

Given an array nums, return true* if the array was originally sorted in non-decreasing order, then rotated some number of positions (including zero)*. Otherwise, return false.

There may be duplicates in the original array.

Note: An array A rotated by x positions results in an array B of the same length such that A[i] == B[(i+x) % A.length], where % is the modulo operation.

 

Example 1:

**Input:** nums = [3,4,5,1,2]
**Output:** true
**Explanation:** [1,2,3,4,5] is the original sorted array.
You can rotate the array by x = 3 positions to begin on the the element of value 3: [3,4,5,1,2].

Example 2:

**Input:** nums = [2,1,3,4]
**Output:** false
**Explanation:** There is no sorted array once rotated that can make nums.

Example 3:

**Input:** nums = [1,2,3]
**Output:** true
**Explanation:** [1,2,3] is the original sorted array.
You can rotate the array by x = 0 positions (i.e. no rotation) to make nums.

 

Constraints:

1 <= nums.length <= 100
1 <= nums[i] <= 100

class Solution:
    def check(self, nums: List[int]) -> bool:
        inflextion = False
        for idx, k in enumerate(nums):
            if idx == 0:
                continue
            if k < nums[idx-1] and  inflextion:
                return False
            if k >= nums[idx-1] and not inflextion:
                continue
            else :
                inflextion = True

        if inflextion and nums[-1] > nums[0]:
            return False
        return True