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From: Keith Thompson <kst-u@mib.org>
Newsgroups: comp.lang.c
Subject: Re: "usual arithmetic conversions": please explain something...
Date: Tue, 28 Feb 2017 18:51:03 -0800
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Ben Bacarisse <ben.usenet@bsb.me.uk> writes:
> Keith Thompson <kst-u@mib.org> writes:
> <snip>
>>> On 28/02/2017 23:33, Lowell Gilbert wrote:
>>>> Given the following program:
>>>>
>>>>     #include <stdio.h>
>>>>
>>>>     int main (void)
>>>>     {
>>>>             unsigned long a = 4000;
>>>>             signed long b = -10;
>>>>             int c;
>>>>
>>>>             c = a * b;
>>>>             printf("%d\n", c);
>>>>
>>>>             return 0;
>>>>     }
> <snip>
>> But do try:
>>
>>     printf("%llu\n", a * b);
>
> A small point, but the product is of type unsigned long so %lu is the
> right format.

You're right, of course.  Not sure why I added the extra "l".

>> That will show you the actual value that's converted to int before being
>> stored in c.
>
> <snip>

-- 
Keith Thompson (The_Other_Keith) kst-u@mib.org  <http://www.ghoti.net/~kst>
Working, but not speaking, for JetHead Development, Inc.
"We must do something.  This is something.  Therefore, we must do this."
    -- Antony Jay and Jonathan Lynn, "Yes Minister"