# start line with a sharp char for comments that will be echoed in the execution report.
# level sequence for trees: the vertex labels are listed side by side, following
# branches of your graph. Every time a label repeats, a new branch is considered. 
# with 6 vertices
0-1-2-3-1-4-2-5
# with 8 vertices
0-1-2-1-2-4-5-4-6-7
# with 10 vertices
0-1-2-3-1-4-5-6-5-7-8-9
# with 12 vertices
0-1-2-3-4-1-5-6-7-8-5-9-10-3-11