AtCoder Beginner Contest 136
翻译中…
Problem Statement
翻译中…
Given is an integer $N$. Find the number of positive integers less than or equal to $N$ that have an odd number of digits (in base ten without leading zeros).
翻译中…
Constraints
翻译中…
$1 \leq N \leq 10^5$
翻译中…
Input
翻译中…
Input is given from Standard Input in the following format:
翻译中…
N翻译中…
Output
翻译中…
Print the number of positive integers less than or equal to $N$ that have an odd number of digits.
翻译中…
样例
Input #1
11
Output #1
9
Among the positive integers less than or equal to $11$, nine integers have an odd number of digits: $1, 2, \ldots, 9$.
Input #2
136
Output #2
46
In addition to $1, 2, \ldots, 9$, another $37$ integers also have an odd number of digits: $100, 101, \ldots, 136$.
Input #3
100000
Output #3
90909
题目信息
题面与样例版权归 AtCoder 及出题人所有；中文翻译由 AI 生成（CI 管线），如有出入请以原文为准。