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Curry
 one year ago
Can someone check my work? Show by counterexample that the statement, “To subtract b from a in
a computer with a 4bit, one’s complement architecture, simply negate
b and add it to a” does not hold for all integers a and b.
Curry
 one year ago
Can someone check my work? Show by counterexample that the statement, “To subtract b from a in a computer with a 4bit, one’s complement architecture, simply negate b and add it to a” does not hold for all integers a and b.

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Curry
 one year ago
Best ResponseYou've already chosen the best response.0I'm a bit confused, so any help?

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0Are you using sublime?

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0I think that the correct ones compliment for b is 1001

Curry
 one year ago
Best ResponseYou've already chosen the best response.0yes, i am using sublime 2.

Curry
 one year ago
Best ResponseYou've already chosen the best response.0but 1011 should evaluate to 4 right? not 3. Since it's one's complement architecture?

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0Yeah, it should be 4

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0I'm wondering if one's complement architecture uses the same addition algorithm

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0Since 1111 would be 0 (0), then you would have 0001 + 1111 = 0000 which would say 1+ 0 = +0, but this doesn't seem correct since we should really have an answer of 1.

Curry
 one year ago
Best ResponseYou've already chosen the best response.0no no we shouldn't have an answer of one. that's what the question tells us. to give a counter example that doesn't work when dealing with just 4 bit architecture.

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0So I think that if 1's complement has a carry, then it needs to be added back into our new number. So 1111 + 0001 = 1 0000. The carry 1 gets added back in to get us 0001, so our answer is 1

Curry
 one year ago
Best ResponseYou've already chosen the best response.0oh sorry, i misreaed your previous comment. ok ok, so if there is a carry over like that, then it gets added back in. I don't know how that work sin the computer but i'll kkep it in mind.

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0Well, I might be wrong

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0Okay it looks like if b > a, then you'll need to do a borrow, and so simply doing ones complement and adding will not work.

rsmith6559
 one year ago
Best ResponseYou've already chosen the best response.0FWIW, capture.png shows and answer of +11 plus the carry. If the carry triggered a one's compliment conversion, wouldn't that give you the answer? How you could tell 11 from +8 eludes me.
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