Sorting Strings that contains number in Java [duplicate]

Answer 1

You can implement a comparator and pass it to the set constructor. See http://docs.oracle.com/javase/1.4.2/docs/api/java/util/Comparator.html.

If all your strings are in the form of room[number] you can strip the "room" parse the number and compare by it.
Alternatively - you can store Integers in you set and print them with "room" prefix.