Will someone know why so happened? Кто-нибудь мне объяснит почему так происходит

Question

Когда я ввожу / input
18
7 7 7 7 7 7 7 5 5 5 5 5 4 4 4 4 8 8
У меня выходит / Output
15
4 8 8
А когда я ввожу / and when I enter
Input:
7 7 7 7 7 7 7 5 5 5 5 5 2 2 2 2 8 8
У меня выходит / I get such a Output
16
8 8

Я просто заменил число 4 на 2,а в результате такой ответ. Хотя 4 на 2 никак не связаны/ I just replaced a number 4 on 2, though these numbers have not connection
https://code.sololearn.com/c0EvIzyW39eb/?ref=app
https://code.sololearn.com/c0EvIzyW39eb/?ref=app

Answer 1

Line 13 saves the 5 in x, line 19 subtracts one from x making it 4, line 15 tests x against a[i]. That test succeeds for your first input and fails for the second. Change 5s to 3s and it should run similar.

Answer 2

Not without a description of input, expected output, and some idea of what it is trying to do as I have no idea. I just added debugging statements telling me variable values and if statement path. Once I knew the path taken between the two runs, it was easy to figure out why. After line 6, with indenting added:
print(i, a[i], k, x, lst, end = "")
After lines 7, 9, 15, and 18, added print of line number like:
print(" 7")

Answer 3

Can you correct in my code my mistakes and past there please?