TTsurutani
commented
6 years ago Task Given a positive integer n, count the number of digits of all numbers in the range 0 < x < 10^n.
Code Limit At most 70 characters.
Protip: At least 26 characters will be devoted to other stuff.
Example f(1) = 9 f(9) = 8888888889
https://www.codewars.com/kata/one-line-task-how-many-digits/train/haskell