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From: Tim Rentsch <tr.17687@z991.linuxsc.com>
Newsgroups: comp.lang.c
Subject: Re: Increment/decrement a variable with a maximum
Date: Sun, 18 Dec 2022 16:41:14 -0800
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pozz <pozzugno@gmail.com> writes:

> Suppose you have two uint32_t variables (a and b) that you want to add
> together and another uint32_t variable (max) that is the maximum that
> the result could assume.  A silly code could be:
>
>   a += b;
>   if (a > max) {
>     a = max;
>   }
>
> Of course, this doesn't work well for every values of a, b and max.
>
> For example, for a=0xFFFF'FFFC, b=10 and max=0xFFFF'FFFE.
>
>
> Could you suggest a better method?  [...]

    a =   max > a  &&  max - a > b   ? a + b   : max;

> And for decrement?

After seeing the expression for increment, exercise for the
reader.