Arithmetic Using Simulated Qubits - Brain Theory from a Circuits and Systems Perspective - page 122

Fig. 7.15 Subtractor to determine if b a

Fig. 7.16 Control circuit to determine the greatest priority

meaning of the expression d(e) b(a) is that the larger of a, b is subtracted from

the larger of d, e. This operation requires a control circuit as in Fig. 7.16 .
A neural router, router 1, is defined that will apply the larger of d, e.Ifd

e, its
true C out is applied to a double controlled NOT to copy d 2 , d 1 , d 0 to the B-input of a
reversible adder. But if C out ¼ d at the

bottom of the figure. This is applied to a double controlled NOT to copy e 2 , e 1 , e 0 to
the B input as shown in the bottom portion of the figure.
Similarly if a

0 a toggle is employed to indicate that e >

1 is applied to a double controlled NOT to copy a 2 ,
a 1 , a 0 to the A-input of the reversible adder. But if C out ¼

b, its C out ¼

0 a NOT toggle device is

employed to indicate the b a at the bottom of the figure. This is applied to a

double controlled NOT to copy b 2 , b 1 , b 0 to the A-input as shown in the upper
portion of the figure. This time, a 2's complement is taken of a 2 , a 1 , a 0 or b 2 , b 1 , b 0 .
This is accomplished by applying logical ones to each input line for the A-inputs,

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