PROGRAMMING:Task 10-01-01 count the number of numeric characters
Task 10-01-01 count the number of numeric characters
###Task description
```
Input a line of characters and count the number of digital characters.
```
###Input format:
```
A line of string with a total length of no more than 255.
```
###Output format:
```
Output for 1 line, the number of numeric characters in the output string.
```
###Input example:
```in
Peking University is set up at 1898.
```
###Output example:
```out
four
```
###Title Source
This topic is selected from openjudge website http://noi.openjudge.cn/ch0107/01/
answer：If there is no answer, please comment
###Task description
```
Input a line of characters and count the number of digital characters.
```
###Input format:
```
A line of string with a total length of no more than 255.
```
###Output format:
```
Output for 1 line, the number of numeric characters in the output string.
```
###Input example:
```in
Peking University is set up at 1898.
```
###Output example:
```out
four
```
###Title Source
This topic is selected from openjudge website http://noi.openjudge.cn/ch0107/01/
answer：If there is no answer, please comment