118 lines
5 KiB
HTML
118 lines
5 KiB
HTML
<!doctype html>
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<html lang="en">
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<head>
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<meta charset="UTF-8" />
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<meta http-equiv="X-UA-Compatible" content="IE=edge" />
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<meta name="viewport" content="width=device-width, initial-scale=1" />
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<link rel="stylesheet" href="/styles/common.css" />
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<link rel="stylesheet" href="/styles/post.css" />
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<link rel="icon" type="image/webp" href="/public/logo.webp" />
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<link href="/public/prism/prism.css" rel="stylesheet" />
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<link href="/public/prism/prism-theme.css" rel="stylesheet" />
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<script defer src="/public/prism/prism.js"></script>
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<script
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src="https://cdn.jsdelivr.net/npm/mathjax@3/es5/tex-mml-chtml.js"
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async
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></script>
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<title>Barrett Ruth</title>
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</head>
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<body class="graph-background">
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<header>
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<a
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href="/"
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style="text-decoration: none; color: inherit"
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onclick="goHome(event)"
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>
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<div class="terminal-container">
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<span class="terminal-prompt">barrett@ruth:~$ /algorithms</span>
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<span class="terminal-cursor"></span>
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</div>
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</a>
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</header>
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<main class="main">
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<div class="post-container">
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<header class="post-header">
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<h1 class="post-title">Practice Makes Perfect</h1>
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<p class="post-meta">
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<time datetime="2024-06-22">05/07/2024</time>
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</p>
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</header>
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<article class="post-article">
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<div>
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Today I improved my implementation skills with
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<a
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href="https://codeforces.com/contest/1833/problem/G"
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target="_blank"
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>Codeforces Round 874 Div. 3 Problem G</a
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>. Despite not solving the problem after a full 45 minutes, I came
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across to the following realizations:
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</div>
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<ol>
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<li>
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Don't jump into coding. <i>Fully</i> flesh out your implementation
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in your head before you begin. This is tempting to do, especially
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in a "competitive" environment. I tend to do this to avoid
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thinking about troublesome aspects of the problem that I
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<i>know</i> I'll have to face later. Going into problems with a
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plan makes things much easier when coding but much harder up
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front. It is easy (for me) to get lost in the black-boxing four layers deep. Write it out, visualize it, and practice practice practice.
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<blockquote>
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Considering my solution would've led to me uncover my core
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misinterpretation of the problem:
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<b>the tree does not have to binary</b>. I developed a solution
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for binary trees but the greedy logic cannot be extended to
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trees.
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</blockquote>
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</li>
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<li>
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Complex problems are, well, hard. You <i>have</i> to practice to
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internalize patterns so you can focus on the <i>crux</i> of the
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problem.
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<blockquote>
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I spent 10 minutes debugging retrieving the leaves of a tree
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before even beginning to code the actual algorithm.
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<b>1800 is out of my skill range</b> (for now!).
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</blockquote>
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</li>
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<li>
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<b>Do not let a single thought/assertion/fact go unturned</b>. I
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made a litany of erroneous assertions in my time thinking about
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this problem, some of which include:
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</li>
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<ul>
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<li>The tree has to be binary (it does not).</li>
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<li>
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I can gather the leaves in arbitrary order (once again, this
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doesn't generalize to trees).
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</li>
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<li>
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Ignore all cuts between identical nodes—it's fine! (I
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didn't know why this was the case)
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</li>
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<li>
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A set shouldn't be needed to track visited nodes in a
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tree— slap it on anyway (this was superfluous and
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should've immediately set off red flags that my parent-ignoring
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policy in my BFS was wrong).
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</li>
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<li>
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When processing a node in the "child-parent-child" pattern, just
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pop off the next node from the queue (within binary/n-ary trees,
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this is wrong—the leaves are gathered by <i>level</i>, so
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the next node in the queue is not guaranteed to be the current's
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sibling).
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</li>
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</ul>
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<li>
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Just because the solution passes the test cases does not mean it
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is right. This specifically applies to problems near/outside your
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skill range—create your own test cases.
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</li>
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</ol>
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</article>
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</div>
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</main>
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<script src="/scripts/common.js"></script>
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<script src="/scripts/post.js"></script>
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</body>
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</html>
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