Hello all,
I'm interested in extending Tutorial 4 to have multiple s-trees off
the root.  I'd like to have each s-tree calculate an output variable
that I can use to feed in to an external fitness function.

For example:
tree a: x*x+y*y
tree b: x*x*x+y*y*y

For every run of the GP I can then pass the results of a and b (output
vars) and x and y (input vars) to an external function to generate the
result variable.

My java OOP is a bit sketchy - does anybody have a snip of code to
extend the file (and perhaps in tutorial 4 to accomplish this?