CF373B Making Sequences is Fun

We'll define $ S(n) $ for positive integer $ n $ as follows: the number of the $ n $ 's digits in the decimal base. For example, $ S(893)=3 $ , $ S(114514)=6 $ . You want to make a consecutive integer sequence starting from number $ m $ ( $ m,m+1,... $ ). But you need to pay $ S(n)·k $ to add the number $ n $ to the sequence. You can spend a cost up to $ w $ , and you want to make the sequence as long as possible. Write a program that tells sequence's maximum length.

The first line contains three integers $ w $ ( $ 1

The first line should contain a single integer — the answer to the problem.