# Created by Egor Kostan.
# GitHub: https://github.com/ikostan
# LinkedIn: https://www.linkedin.com/in/egor-kostan/
[docs]def first_non_consecutive(arr: list):
"""
Find the first element of an array that is not consecutive.
E.g. If we have an array [1,2,3,4,6,7,8] then 1 then 2 then 3
then 4 are all consecutive but 6 is not,
so that's the first non-consecutive number.
If the whole array is consecutive then return null or Nothing.
:param arr:
:return:
"""
for index, n in enumerate(arr):
if index + 1 < len(arr) and n + 1 != arr[index + 1]:
return arr[index + 1]