$3.$ Consider an Illiac mesh $(8\backslash$times $8),$ a binary hypercube, and a barrel shifter, all$$with $64$ nodes labeled N$0,$N$1,...,$N$63.$ All network links are bidirectional.$1$ List all the nodes reachable from node N$0$ in exactly three steps for$$each of the three networks.$$ Indicate in each case the tightest upper bound on the minimum number$$of routing steps needed to send data from any node Ni to another node$$Nj $.$