Kirupa's Abstract Data Types Tutorial

Its been a while since my last post, i’ve been very busy with my school and work that i barely have time to open flash.

Here’s my Question:

Can somebody tell if its posible to make an edge just one way and how ?

An example of what im asking for its like this:

Let’s pretend i have 3 nodes: a, b and c, and 3 edges “a-b”, “b-c”, and “c-a”

if i select a and c the path selected is “c-a” instead of “a-b”, “b-c”.