5855: Making Sequences is Fun

内存限制:256 MB 时间限制:2 S
题面:传统 评测方式:文本比较 上传者:
提交:0 通过:0

题目描述

time limit per test
2 seconds
memory limit per test
256 megabytes
input
standard input
output
standard output

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(nk 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.

Input

The first line contains three integers w (1≤w≤1016), m (1≤m≤1016), k (1≤k≤109).

Please, do not write the %lld specifier to read or write 64-bit integers in C++. It is preferred to use the cin, cout streams or the %I64d specifier.

Output

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

Examples
Input
9 1 1
Output
9
Input
77 7 7
Output
7
Input
114 5 14
Output
6
Input
1 1 2
Output
0