Writes PYTHON Function

def solution(elements):

#Implement

For two arrays a and b of the same length, let's say a is a cyclic shift of b, if it's possible for a to become equal to b by performing cyclic shift operations on a - moving 0 or more elements from the beginning of the array to the end of the array without changing the order of the elements.

You are given an array of integers elements. Your task is to check whether elements is a cyclic shift of the sorted array [1, 2, ..., elements.length]. Return the number of elements you need to move to make elements equal to the sorted array. If elements is not a cyclic shift of the sorted array (it's not possible to make them equal), return -1.

Expand to see the example video.

Example

• For elements = [1, 4, 2, 3], the output should be solution(elements) = -1.

  Let's consider all possible cyclic shifts of elements that could make it equal to the sorted array:

  • Moving 0 elements from the beginning to the end, we get [1, 4, 2, 3].
  • Moving 1 elements from the beginning to the end, we get [4, 2, 3, 1].
  • Moving 2 elements from the beginning to the end, we get [2, 3, 1, 4].
  • Moving 3 elements from the beginning to the end, we get [3, 1, 4, 2].

  None of these cyclic shifts equal the sorted array [1, 2, 3, 4], so the answer is -1.

• For elements = [3, 4, 5, 1, 2], the output should be solution(elements) = 3.

  If we move the first 3 elements of the given array from the beginning to the end, we get [1, 2, 3, 4, 5], which is equal to the sorted array [1, 2, 3, 4, 5], so the answer is 3.

Input/Output

• [execution time limit] 4 seconds (py3)

• [input] array.integer elements

  An array of integers.

  Guaranteed constraints: 3 elements.length 100, 1 elements[i] elements.length.

• [output] integer

  Return the number of elements required to perform the cyclic shift on elements that will make it equal to the sorted array [1, 2, ..., elements.length]. If it's not possible to make these arrays equal after performing cyclic shift operations, return -1

Input:

elements: [1, 4, 2, 3]

Expected Output:

-1

Input:

elements: [3, 4, 5, 1, 2]

Expected Output:

3