Hi everyone I want to propose a new challenge, although I'm not sure if it is up to your capabilities because I have seen so many excellent and great programers here and probably this is a very small task for you guys. but here it is, I want you to create a closed polyline that contains all the lines or polylines selected kind of create a boundary.
As you may know I already have my own program that solves the task, and I'll show it later on, so hope you enjoy your small challenge.
I leave a dwg file to make your own trials, here is also a gif that shows how I do it, most surely you can do it much better.