impressive

there's no problems with comparing characters in the strings.

Nicely done

Не совсем верное решение.. Если сравнивать в строке будет не правильный вывод. Нужно сравнивать в Int. Не ужели только я заметил, меня вообще возмутило сравнение в str. И как прошло тесты такое решение?

a nice tap!

I'm so happy that my solution is the same! Thank you :)

Just now learned I can iterate using .join without 'for'. Thanks!

This is cool I didn't know you could do that.

I went over and made a list to do all this! Brilliant

which one

immaculate

Elementary

nice radix conversion from int to string

counting matches of '1' is simple, and could easily scale to higher radixes such as octal
could easily be extended to match multiple digits, such as .count('137')

range traversal is clear

accumulator function sum() over a list is also a nice aggregate function

nah

Clever, but this code is less readable than if you split it into several functions with explicit names.