trees??

[chelle31]

How do you make an array based tree? I was asked to make a tree from an expression that will be inputted by the user and I have no clue how to go about this project!

[CaptainPinko]

what do you want to do exactly?

[Dillinger4]

chelle31 i am assuming that you are refering to a data structure such as a Vector or a TreeSet all of which can be found within java.util A TreeSet implements the SortedSet interface whereas a Vector implements the List interface. The difference between a List and a Set is that a List allows duplicates and maintains order whereas a Set does not allow duplicates and does not maintain order. So if you do not want duplicates and want to maintain order you would want to go with using a TreeSet which implements the SortedSet interface.

As for your project did your teacher give you any additional information?

For the time being here is an example of how to bridge the gap between arrays and Collections. Use the toArray() method found in the Collection interface and the asList() method found in theArray class.

 
Set tvset = new HashSet(Arrays.asList(xarray));
String[] digitalarray = (String[]) tvset.toArray(new String[0]);