Score : $500$ points

问题陈述

求 $\displaystyle \sum_{k=0}^{10^{100}} \left \lfloor \frac{X}{10^k} \right \rfloor$.

以上为通义千问 qwen-max 翻译，仅供参考。

Problem Statement

Find $\displaystyle \sum_{k=0}^{10^{100}} \left \lfloor \frac{X}{10^k} \right \rfloor$.

Notes

$\lfloor A \rfloor$ denotes the value of $A$ truncated to an integer.

Constraints

• $X$ is an integer.
• $1 \le X < 10^{500000}$

Input

Input is given from Standard Input in the following format:

$X$

Output

Print the answer as an integer.
Here, the answer must be precisely printed as an integer, even if it is large. It is not allowed to use exponential notation, such as 2.33e+21, or print unnecessary leading zeros, as in 0523.

Sample Input 1

1225

Sample Output 1

1360

The value we seek is $1225+122+12+1+0+0+\dots+0=1360$.

Sample Input 2

99999

Sample Output 2

111105

Beware of carries.

Sample Input 3

314159265358979323846264338327950288419716939937510

Sample Output 3

349065850398865915384738153697722542688574377708317

The values in input and output can both be enormous.

update @ 2024/3/10 10:09:00