PROGRAMMING:Chenyang brother's games

Today, brother Chenyang was very boring. He thought of a funny little game. Input a string (length less than 100, the string is only composed of letters), convert upper case letters to lower case letters, and then output them in alphabetical order.
###Input format:
There are several groups of test data, which are processed to the end of the file. Each group enters a string.
###Output format:
Convert to lowercase and sort the string.
###Input example:
Here is a set of inputs. For example:
```in
cdAB
ACbd
QWERTYUIOPasdfghjklZXCVBNM
```
###Output example:
The corresponding output is given here. For example:
```out
abcd
abcd
abcdefghijklmnopqrstuvwxyz
```







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