5189: Vanya and Books

内存限制:256 MB 时间限制:2 S 标准输入输出
题目类型:传统 评测方式:文本比较 上传者:
提交:0 通过:0

题目描述

B. Vanya and Books
time limit per test
1 second
memory limit per test
256 megabytes
input
standard input
output
standard output
Vanya got an important task − he should enumerate books in the library and label each book with its number. Each of the n books should be assigned with a number from 1 to n. Naturally, distinct books should be assigned distinct numbers.
Vanya wants to know how many digits he will have to write down as he labels the books.
Input
The first line contains integer n (1≤n≤109) − the number of books in the library.
Output
Print the number of digits needed to number all the books.
Examples
Input
13
Output
17
Input
4
Output
4
Note
Note to the first test. The books get numbers 1,2,3,4,5,6,7,8,9,10,11,12,13, which totals to 17 digits.
Note to the second sample. The books get numbers 1,2,3,4, which totals to 4 digits.

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