Re: Suggested method for returning a string from a C program?

DFS <nospam@dfs.com> writes:

On 3/19/2025 4:53 AM, Keith Thompson wrote:

Ike Naar <ike@sdf.org> writes:

On 2025-03-19, DFS <nospam@dfs.com> wrote:

>

I'm doing these algorithm problems at
https://cses.fi/problemset/list/

>
>

I've been playing with some of these myself. 

>
Are you just looking for ones you find interesting?
>
I'm starting at the top and going down 1 by 1, no matter how simple.

I started at the top.  I'm not sure how long I'll continue.

I'm actually using
scanf() for integer input, something I wouldn't do in normal code
(because the behavior is undefined if the scanned value is out
of range).  This is a rare case where it's safe to assume that
stdin has nothing harmful.

>
>
>
My very 1st submission for 'Missing Number' was accepted, but each use
of scanf() generated a warning:
>
warning: ignoring return value of 'scanf' declared with attribute
'warn_unused_result' [-Wunused-result]
   30 |         scanf("%d", &nums[i]);

I got the same warning.  scanf() returns the number of items that were
successfully scanned, and you should **always** check that result in
real world code.  This autotester, which strictly constrains the input
your program will receive, is an exception, but the warning is a good
one.  And of course if you want to make your submitted program more
robust, that's a good exercise, though the site won't give you extra
points for that.

spoiler: code below

[...]

//identify the missing number in a set of consecutive integers

[code snipped]

I used a different approach.  I'll encode the description of the
solution using rot13.

The program is given an integer n and a list of n-1 integers, not
necessarily ordered.

The task is to determine which number is missing from the list.

Gurer'f n jryy xabja sbezhyn sbe gur fhz bs nyy a ahzoref sebz bar
gb a.  Pbzchgr gur rkcrpgrq fhz, gura fhogenpg gur fhz bs gur ahzoref
tvira ba gur frpbaq vachg yvar.  Gur qvssrerapr vf gur zvffvat ahzore.

--
Keith Thompson (The_Other_Keith) Keith.S.Thompson+u@gmail.com
void Void(void) { Void(); } /* The recursive call of the void */