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feat(cp): codeforces 900 div 3

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Barrett Ruth 2025-03-22 15:50:49 -04:00
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@ -35,6 +35,60 @@
<h1 class="post-title">Competitive Programming Log</h1> <h1 class="post-title">Competitive Programming Log</h1>
</header> </header>
<article class="post-article"> <article class="post-article">
<h2>
<a href="https://codeforces.com/contest/1878/" target="_blank"
>900 (div. 3)</a
>&mdash;22/3/2025
</h2>
<div>
<p>
Solved in a coffee shop. Used AI for smaller things (otherwise I'd
have no idea).
</p>
<ul>
<li>
A: Solved a much harder problem related to majority element
paths on tree&mdash;realized the solution after a minute.
</li>
<li>
B: was confused for about 7 minutes but realized some properties
of divisibility and odd numbers.
<b
>Math is still a weakness. Take simpler approaches to complex
constraints, such as considering parity.</b
>
</li>
<li>
Went off of gut instinct that it is always possible to form the
given \(x\) if encompassed in the range of numbers.
<b
>Failed to prove this mathematical validity but had fair
intuition</b
>
(i.e. just "take off one" if too big/small). This is acceptable,
though not perfect.
</li>
<li>
D: cooked. Solved E first and had mentally given up by this
point.
<b
>If you've given up, just stop trying and take a break/do
something else. You're wasting your time.</b
>
</li>
<li>
E: incredibly easy with segtree. Realized the lower bound/walk
solution after 2-3 minutes. Binary search indexing can be
improved (i.e. which pointer to return?) as well as realizing
one binary search is necessary across both arrays. Good
mathematical deduction to realize relationship between input
arrays. Revisit sparse table + simpler solution&mdash;<i
>don't be content with an advanced solution when a
simpler/elegant idea also suffices</i
>.
</li>
</ul>
</div>
<h2> <h2>
<a href="https://codeforces.com/contest/1857/" target="_blank" <a href="https://codeforces.com/contest/1857/" target="_blank"
>891 (div. 3)</a >891 (div. 3)</a
@ -111,7 +165,10 @@
but thanks Deepseek). but thanks Deepseek).
<b>Overflow, again. rly dude?</b> <b>Overflow, again. rly dude?</b>
</li> </li>
<li>F: doing this later, got the core insight of the minimal weight edge path. Once again, for surveying path </li> <li>
F: doing this later, got the core insight of the minimal weight
edge path. Once again, for surveying path
</li>
</ol> </ol>
</div> </div>
<h2>cses (range queries, sorting and searching)&mdash;1/3/2025</h2> <h2>cses (range queries, sorting and searching)&mdash;1/3/2025</h2>