got the waittimes to work for the A>C>D and B>C>D testcase, but not for
the A>C>D and B>C>A testcase. indices are mismatched or something. also,
the output for path + waittimes is something like [A, C, D] [0, 0, 1]
when it should be [A, C, D] [0, 1, 0]. perhaps waittimes should be one
index shorter than nodes or something. in any case, there's a small
problem when a train is coming from another train's destination node in
which the system realizes that the A node is only one from the C node,
even though that's not a conflic region. not 10)% sure if it should work
anyway or not. must spend more time on it.