
I would like you to implement a module named TopModule with the following
interface. All input and output ports are one bit unless otherwise
specified.

 - input  clock
 - input  a
 - output p
 - output q

The module should implement a sequential circuit. Read the simulation
waveforms to determine what the circuit does, then implement it.

  time   clock   a   p   q
  0ns    0       0   x   x
  5ns    0       0   x   x
  10ns   0       0   x   x
  15ns   0       0   x   x
  20ns   0       0   x   x
  25ns   1       0   0   x
  30ns   1       0   0   x
  35ns   1       0   0   x
  40ns   1       0   0   x
  45ns   1       0   0   x
  50ns   1       0   0   x
  55ns   0       0   0   0
  60ns   0       0   0   0
  65ns   0       0   0   0
  70ns   0       1   0   0
  75ns   0       0   0   0
  80ns   0       1   0   0
  85ns   1       0   0   0
  90ns   1       1   1   0
  95ns   1       0   0   0
  100ns  1       1   1   0
  105ns  1       0   0   0
  110ns  1       1   1   0
  115ns  0       0   1   1
  120ns  0       1   1   1
  125ns  0       0   1   1
  130ns  0       1   1   1
  135ns  0       0   1   1
  140ns  0       0   1   1
  145ns  1       0   0   1
  150ns  1       0   0   1
  155ns  1       0   0   1
  160ns  1       0   0   1
  165ns  1       1   1   1
  170ns  1       0   0   1
  175ns  0       1   0   0
  180ns  0       0   0   0
  185ns  0       1   0   0
  190ns  0       0   0   0

