A sequential circuit with two clocked D$-$flip$-$flops A and B$,$ one input x $,$ and one output z is specified by the following input equations:

D

A

$=$

B

$$

$$

x

D

A

$$

$=$B

$$

$$x $,$

D

B

$=$

A

$$

x

D

B

$$

$=$A$$x $,$

z

$=$

A

$$

$$

B

z$=$A

A sequential circuit with two clocked D$-$flip$-$flops A and B$,$ one input x $,$ and one output z is specified by the following input equations:

D

A

$=$

B

$$

$$

x

D

A

$$

$=$B

$$

$$x $,$

D

B

$=$

A

$$

x

D

B

$$

$=$A$$x $,$

z

$=$

A

$$

$$

B

z$=$A

$$

$$