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Groups > comp.lang.c > #168606

Re: Increment/decrement a variable with a maximum

From Kaz Kylheku <864-117-4973@kylheku.com>
Newsgroups comp.lang.c
Subject Re: Increment/decrement a variable with a maximum
Date 2022-12-20 13:44 +0000
Organization A noiseless patient Spider
Message-ID <20221220053840.192@kylheku.com> (permalink)
References <tno602$2cj2$1@dont-email.me>

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On 2022-12-18, pozz <pozzugno@gmail.com> wrote:
> 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.

if (a + b > a || a + b > max)
  a = max;
else
  a = a + b; // written this way to make common subexpression obvious

-- 
TXR Programming Language: http://nongnu.org/txr
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Thread

Increment/decrement a variable with a maximum pozz <pozzugno@gmail.com> - 2022-12-18 23:59 +0100
  Re: Increment/decrement a variable with a maximum Siri Cruise <chine.bleu@yahoo.com> - 2022-12-18 15:07 -0800
  Re: Increment/decrement a variable with a maximum Richard Damon <Richard@Damon-Family.org> - 2022-12-18 19:25 -0500
  Re: Increment/decrement a variable with a maximum Tim Rentsch <tr.17687@z991.linuxsc.com> - 2022-12-18 16:41 -0800
  Re: Increment/decrement a variable with a maximum antispam@math.uni.wroc.pl - 2022-12-19 14:39 +0000
  Re: Increment/decrement a variable with a maximum Kaz Kylheku <864-117-4973@kylheku.com> - 2022-12-20 13:44 +0000
    Re: Increment/decrement a variable with a maximum Kaz Kylheku <864-117-4973@kylheku.com> - 2022-12-20 13:54 +0000
    Re: Increment/decrement a variable with a maximum Jame O' Brian <invalid@gmail.com> - 2022-12-20 18:12 +0000
      Re: Increment/decrement a variable with a maximum Lew Pitcher <lew.pitcher@digitalfreehold.ca> - 2022-12-20 18:21 +0000
      Re: Increment/decrement a variable with a maximum "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2022-12-20 12:52 -0800
        Re: Increment/decrement a variable with a maximum Öö Tiib <ootiib@hot.ee> - 2022-12-23 05:21 -0800
          Re: Increment/decrement a variable with a maximum "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2022-12-23 13:53 -0800

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