a difficult control input question

[transgalactic]

**broken link removed**

the main problem comes when in one input i need to divide the number by 2
(subtract a zero from the original input)

while in other control input i need to multiply by two
(which meens to add a zero to the original input)

i dont know how to delete or add an output
when i have a certain control input

the number of outputs is constant

what should i do??

 

[mneary]

To divide, shift a zero in from the left, causing the least significant bit to be lost to the right. To multiply, shift a zero in from the right, causing a bit to be lost on the left. The problem with multiply is that if the multiply results in an overflow, the bit lost on the left (1) is gone forever and the answer is wrong.

 

[transgalactic]

but i dont have a shift register.
i need to implement it using four MUX 4-1 three AND two OR

how to build it using these components
?????