Why here we don’t take -2^n *Z[n] as part of the solution.

And I would be thankful if u gave me a pubic idea about what the circ do.

In order to understand what the circuit does, you can do a small simulation with two small strings and see what you get for them.

We kind of solved this question in recitation 11.

Z[n:0] is the representation in two’s complement of the number we get from the calculation of A and B.

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