Inputs Xi and Yi of each full adder in an arithmetic circuit have digital logic specified by the Boolean functions
Xi = Ai
Yi = B'iS + Bi C'in
where S is a selection variable, Cin is the input carry, and Ai and Bi are input data for stage i.
(a) Draw the logic diagram for the 4-bit circuit, using full adders and multiplexers.
(b) Determine the arithmetic operation performed for each of the four combinations of S and Cin: 00, 01, 10, and 11.
Handwritten logic diagrams with the resulting arithmetic operations in a table.