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From: Tim Rentsch <tr.17687@z991.linuxsc.com>
Newsgroups: comp.lang.c
Subject: Re: OT: CSES Number Spiral algorithm
Date: Thu, 20 Mar 2025 11:38:18 -0700
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DFS <nospam@dfs.com> writes:

> I don't have a C question, but rather I'd like input about algorithmic
> approaches.
>
> https://cses.fi/problemset/task/1071
>
> It's an 'infinite grid'.  You have to find the value at rows-columns
> from 1 to 10^9.
>
> First thing you notice about the 5x5 grid is the values in
> odd-numbered columns begin with the square of the column number, and
> the values in even-numbered rows begin with the square of the row
> number.
>
> I followed the number pattern and built a grid in Excel and expanded
> it to 10x10 for more testing.
>
> https://imgur.com/x4VymmA
>
> Then coded 4 conditions      solution
> 1. row <= col and col odd    (col * col) - row + 1
> 2. row <= col and col even   ((col-1) * (col-1)) + row
> 3. row >  col and row odd    ((row-1) * (row-1)) + col
> 4. row >  col and row even   (row * row) - col + 1
>
> My full C code submission was accepted the first time.
>
> How would you have done it?

This posting is not appropriate for comp.lang.c.  Putting "OT" in
the subject line doesn't excuse its lack of suitability.