It can be done with only 3 cables with max value of 1.  Got AC

“You are to help Andrew to find the way to connect hubs so that all above conditions are satisfied.”
So you can output any correct answer.

I got an AC too, with a program outputting only 3 connections for the sample case.
The only thing that actually matters is the very first value of the output - the maximum length of a cable.

Generally it means the problem is much simpler than finding the optimal MST.