We’ll continue our theme of list rotation by flipping the problem: given a sorted list rotated k times, return the index where the “unrotated” list would begin.

rotated_list = ['c', 'd', 'e', 'f', 'a']
rotation_point(rotated_list)
# index 4
# a sorted list would start with 'a'

another_rotated_list = [13, 8, 9, 10, 11] 
rotation_point(rotated_list)
# index 1
# a sorted list would start with 8

Clarifying Questions:

• Are there constraints on time or space efficiency?
  • No! Any solution will do.
• Does the rotation direction matter?
  • This won’t affect the return value.
• What if the input isn’t rotated?
  • Return 0.