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From: Tim Rentsch <tr.17687@z991.linuxsc.com>
Newsgroups: comp.lang.c
Subject: Re: Sort of trivial code challenge - may be interesting to you anyway
Date: Fri, 06 Mar 2026 08:37:35 -0800
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scott@slp53.sl.home (Scott Lurndal) writes:

> Tim Rentsch <tr.17687@z991.linuxsc.com> writes:
>
>> scott@slp53.sl.home (Scott Lurndal) writes:
>>
>>> Tim Rentsch <tr.17687@z991.linuxsc.com> writes:
>>>
>>>> scott@slp53.sl.home (Scott Lurndal) writes:
>>>>
>>>>> DFS <nospam@dfs.com> writes:
>>>>>
>>>>>> On 3/4/2026 5:44 AM, Bonita Montero wrote:
>>>>>>
>>>>>>    int colwidth = sprintf(cw,"%d",max) + 1;
>>>>>
>>>>> using ciel(log10(rows*columns)) performs better than snprintf
>>>>> in this application.
>>>>>
>>>>>
>>>>> $ printf '%f\n' $(( ceil(log10( 8*8)) ))
>>>>> 2.000000
>>>>
>>>> Using snprintf() is more correct and also more obviously correct.
>>>
>>> Yes, I had assumed the first row, first column would be zero, not one.
>>
>> The value for 10 is also wrong.  And 100.  And 1000.  etc...
>
> No, 10*10 yields 100 values from 0 to 99.

You changed the subject.  We were talking about how to
calculate an appropriate field width given a maximum value.
The problem under discussion produces values from 1 to
maximum value, inclusive.  The expression ceil(log10( max ) )
gives wrong answers when max is a power of 10.  I haven't
looked at Bonita Montero's code but based on the snippet
above it seems clear he is responding to the original problem
statement, even if he may have misunderstood what that was
asking for.