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From: David Brown <david.brown@hesbynett.no>
Newsgroups: comp.lang.c
Subject: Re: What is your opinion about unsigned int u = -2 ?
Date: Fri, 9 Aug 2024 20:19:59 +0200
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On 09/08/2024 20:08, Bonita Montero wrote:
> Am 08.08.2024 um 19:47 schrieb David Brown:
> 
>> Think about negating a value.  For two's complement, that means 
>> inverting each bit and then adding 1.  For sign-magnitude, you
>> invert  the sign bit. For ones' complement, you invert each bit.
> 
> But with one's complement you have the same circuits for ading
> and substracting like with unsigned values.

If you are trying to say that for two's complement, "a + b" and "a - b" 
use the same circuits regardless of whether you are doing signed or 
unsigned arithmetic, then that is correct.  It is one of the reasons why 
two's complement became the dominant format.