pulse needed $($as shown by the counter$)$ will cause a $1-$point deduction. If the circuit does not work, you get no points for this circuit building part.

$2.($Subcircuit name: GCD$)$ Build a circuit to find the GCD between two $8-$bit unsigned numbers A and B $,$ where $AB.$ Let A be an $8-$bit register holding the number A $,$ while B be an $8-$bit register holding the number B $.$ After a Logisim reset, the user will manually enter A and B into the registers $($note that A has to be $B),$ and start the clock pulse generator. For each clock pulse coming from the tunnel $"$CP$",$ A will be updated to MAX$(($A$-$B$),$ B$),$ while B will be updated to MIN$(($A$-$B$),$ B$).$ Note that MAX and MIN return any one of the two given argument values if the argument values are the same. The registers must not update any more if the B register has $0($meaning A now has the GCD$).$ Provide answers to the following questions.

a$.(10$ points$)$ Provide the logic formula for the tunnel "Stop CP$".$ If you are using a comparator output, you may use a form like