List</th>	Reason</th>	Organization</th></tr></thead>
NeetCode Roadmap</a></td>	Provides a guided tree to follow based on prerequisites</td>	Tree with solution types</td></tr>
LeetCode 75</a></td>	Provided by leetcode and free (they also have list available to premium users, support them if you’re able)</td>	Grouped by Solution Type</td></tr>
AlgoMaster</a></td>	Has links to an explanation for each solution type before the problems. Has links to solutions for each problem (seems like his) and preloaded search for solutions on YouTube</td>	Grouped by Solution Type</td></tr>
Grind 75 by author of Blind 75</a></td>	Allows customization of plan to the amount of time you have available and can not show what topic is covered by a question for you to practice that skill</td>	Customizable</td></tr> </tbody></table> Recreational</a></h1> If you’re objective is just practice or for fun then working locally can be less annoying than working in the text editor provided. Also if you want to get practice with using your IDE of choice and learning from the autocomplete and docs displayed in the IDE. Then I recommend cargo-leet</a>. It’s a pretty basic download tool that just tries to setup the tests from the description for you. Happy to accept contributions if you’re so included.</p> Google APIs 2025-03-20T00:00:00+00:00 Google Sheets</a></h1> Foreword</a></h2> It’s been a journey trying to decide what would be the most sustainable way to interact with Google’s API for “Google Sheets”. Seems that currently Google is currently developing a client library</a> for rust but it isn’t done yet. My current use case isn’t amenable to a still experimental API thus I decided to use the next best one. Byron</a> setup a repo</a> to generate clients based on Google’s discovery service. He really did a very good job with it and it seems to at present be the best option. I also considered one</a> created by the Oxide Computer Company</a> but decided to use the one Byron created as his also came with a CLI that I could use to better understand how to use it.</p> Using google_sheets4</a></a></h2> Sources:</p> Medium Article</a> by Chris Grounds</li> Auto generated CLI</a> created by Byron</li> </ul> WIP</strong> The project I was going to use this on has been paused but already started the notes so saving them.</p> lettre 2025-03-15T00:00:00+00:00 Sending email using smtp and Gmail</a></h1> They have a pretty clear example</a> on in their crate. I’d just add that you should ensure you have 2 factor authentication enabled and then that will allow you to create an APP password that you can use for this purpose. You’ll also need to enable POP in settings.</p> Delete Old Files Automatically 2025-02-28T00:00:00+00:00 Explanation</a></h1> Source: https://stackoverflow.com/questions/45838304/bash-delete-files-older-than-3-months</a></p> Before you actually run the delete command it might be good to use `-print</code> as below to see what will be deleted. In both commands (the print and delete one):</p>` `PATH</code> should be replaced with the path to the folder you want to do the deletes in.</li>`DAYS</code> should be replaced with the number of days you need.</li> </ul> See also cron</a> for automating the command</p> Preview output via print</a></h1> Format:</p> find</span> PATH</span> -mtime</span> DAYS</span> -type</span> f</span> -print</span></span></code></pre> Example</p> find</span> .</span> -mtime</span> +90</span> -type</span> f</span> -print</span></span></code></pre>Actual delete command</a></h1> find</span> PATH</span> -mtime</span> DAYS</span> -type</span> f</span> -delete</span></span></code></pre> Macros 2025-02-24T00:00:00+00:00 Info Sources</a></h1> Rust Book</a> Declarative Macros with macro_rules! for General Metaprogramming</a> - Explained example of a macro</li> </ul> </li> Rust by Example</a></li> Rust Reference</a> Syntax</a> Designators</a> - Types of designators available (Macro Variable types)</li> </ul> </li> </ul> </li> </ul> Motivation to finally try macros</a></h1> Exercism - Space Age</a></li> </ul> Omit From History 2025-02-20T00:00:00+00:00 Source: https://stackoverflow.com/questions/6475524/how-do-i-prevent-commands-from-showing-up-in-bash-history</a></p> If you want to leave commands out of the history prefix them with whitespace.</p> Enum Conversion 2025-01-19T00:00:00+00:00 Switching back and forth between an Enum and u8</a></h1> Sources:</p> https://stackoverflow.com/a/76785380</a></li> https://stackoverflow.com/a/76299020</a></li> </ul> #</span>!/</span>usr</span>/</span>bin</span>/</span>env</span> -</span>S</span> cargo</span> +</span>nightly</span> -</span>Zscript</span></span> ---</span>cargo</span></span> package</span>.</span>edition </span>=</span> "2021"</span> # </span>Desirable</span> to stop warning but not needed</span></span> [dependencies]</span></span> strum</span> =</span> { version</span> =</span> "0.26.3"</span>, features</span> =</span> [</span>"derive"</span>] }</span></span> ---</span></span> </span> use</span> strum</span>::</span>FromRepr</span>;</span></span> </span> #[derive(</span>FromRepr</span>,</span> Debug</span>,</span> PartialEq</span>)]</span></span> #[repr(</span>u8</span>)]</span></span> enum</span> MyEnum</span> {</span></span> A</span> =</span> 1</span>,</span></span> B</span>,</span></span> C</span>,</span></span> }</span></span> </span> fn</span> main</span>() {</span></span> // u8 to Enum</span></span> let</span> x</span> =</span> MyEnum</span>::</span>from_repr</span>(</span>2</span>);</span></span> assert_eq!</span>(x,</span> Some</span>(</span>MyEnum</span>::</span>B</span>));</span></span> </span> // Enum to u8</span></span> let</span> x</span> =</span> MyEnum</span>::</span>C</span> as</span> u8</span>;</span></span> assert_eq!</span>(x,</span> 3</span>);</span></span> }</span></span></code></pre> vscode 2025-01-04T00:00:00+00:00 In all headings RA means RustAnalyzer</p> Setting features for RA</a></h1> In .vscode/settings.json</code> add:</p> // .vscode/settings.json</span></span> { </span></span> "rust-analyzer.cargo.features"</span>: [</span>"FEATURE1_HERE"</span>,</span> "FEATURE2_HERE"</span>],</span></span> }</span></span></code></pre>Setting target for RA</a></h1> See the example for wasm</a></p> Disable default features for RA</a></h1> // .vscode/settings.json</span></span> { </span></span> "rust-analyzer.cargo.noDefaultFeatures"</span>:</span> true</span></span> }</span></span></code></pre> Wayland or x11? 2024-12-23T00:00:00+00:00 How to know which you are using</a></h1> Source: https://unix.stackexchange.com/questions/202891/how-to-know-whether-wayland-or-x11-is-being-used</a></p> Based on an error message</a> in the rust winit crate I think the easiest way to check is see if either of the environment variables WAYLAND_DISPLAY</code> or WAYLAND_SOCKET</code> is set. And the environment variable DISPLAY</code> should be set if you are on x11. So…</p> You get output on at least one of this if you are on Wayland:</p> echo</span> $WAYLAND_DISPLAY</span></span> echo</span> $WAYLAND_SOCKET</span></span></code></pre> And you should get output on this if you are on x11:</p> echo</span> $DISPLAY</span></span></code></pre> The actual instruction from the site are to run</p> loginctl</span></span></code></pre> Then take the value under session in the first column and insert into <SESSION></code> in the next command</p> loginctl</span> show-session</span> <</span>SESSIO</span>N</span>></span> -p</span> Type</span></span></code></pre> Github Actions 2024-12-23T00:00:00+00:00 Reusing a github action</a></h1> Source: https://docs.github.com/en/actions/sharing-automations/reusing-workflows#calling-a-reusable-workflow</a></p> See source for more details but I’ll focus on the use case I most commonly have, two workflows in the same repo and I want to call one from the other to ensure it runs and succeeds before the other one starts. Example use case can be found at https://github.com/wykies/crates/</a> where the shuttle.yml</code> calls general.yml</code>.</p> In the workflow being called you must have the following in inside of the on</code> section.</p> on</span>: </span></span> workflow_call</span>:</span></span></code></pre> and in the caller you need to have a separate job that put the relative path the called workflow in uses as below:</p> jobs</span>:</span></span> run_tests</span>:</span></span> uses</span>:</span> ./.github/workflows/general.yml</span></span> deploy</span>:</span></span> runs-on</span>:</span> ubuntu-latest</span></span> needs</span>:</span> run_tests</span> # Requires that the other job succeeds before this one will start</span></span> steps</span>:</span></span></code></pre> Regex 2024-12-02T00:00:00+00:00 Capture first match</a></h1> NB: If regex is not executed more than once then you may opt to not use the Cells but they remove the need to recompile the regex.</p> Dependencies (anyhow</code> is not needed by makes the code cleaner)</p> cargo</span> add regex</span></span> cargo</span> add anyhow</span></span></code></pre>use</span> anyhow</span>::</span>Context</span> as</span> _;</span></span> use</span> regex</span>::</span>Regex</span>;</span></span> use</span> std</span>::</span>sync</span>::</span>OnceLock</span>;</span></span> </span> fn</span> main</span>()</span> -></span> anyhow</span>::</span>Result</span><()> {</span></span> static</span> CELL</span>:</span> OnceLock</span><</span>Regex</span>></span> =</span> OnceLock</span>::</span>new</span>();</span></span> let</span> re</span> =</span> CELL</span>.</span>get_or_init</span>(</span>\|\|</span> {</span></span> Regex</span>::</span>new</span>(</span>r"(\d+)"</span>)</span>.</span>expect</span>(</span>"failed to compile static regex that was known at design time"</span>)</span></span> });</span></span> </span> let</span> haystack</span> =</span> "There are 20 bad apples in the batch of 100"</span>;</span></span> let</span> captures</span> =</span> re</span></span> .</span>captures</span>(haystack)</span></span> .</span>with_context</span>(</span>\|\|</span> format!</span>(</span>"failed to find a match in: {haystack:?}"</span>))</span>?</span>;</span></span> let</span> number</span> =</span> captures</span></span> .</span>get</span>(</span>1</span>)</span></span> .</span>with_context</span>(</span>\|\|</span> format!</span>(</span>"failed to extract number from: {haystack:?}"</span>))</span>?</span></span> .</span>as_str</span>();</span></span> // Prints: The number 20 was found in "There are 20 bad apples in the batch of 100"</span></span> println!</span>(</span>"The number {number} was found in {haystack:?}"</span>);</span></span> Ok</span>(())</span></span> }</span></span></code></pre>Capture all matches</a></h1> See notes on Capture first match</a></p> cargo</span> add regex</span></span> cargo</span> add anyhow</span></span></code></pre>use</span> anyhow</span>::</span>Context</span> as</span> _;</span></span> use</span> regex</span>::</span>Regex</span>;</span></span> use</span> std</span>::</span>sync</span>::</span>OnceLock</span>;</span></span> </span> fn</span> main</span>()</span> -></span> anyhow</span>::</span>Result</span><()> {</span></span> static</span> CELL</span>:</span> OnceLock</span><</span>Regex</span>></span> =</span> OnceLock</span>::</span>new</span>();</span></span> let</span> re</span> =</span> CELL</span>.</span>get_or_init</span>(</span>\|\|</span> {</span></span> Regex</span>::</span>new</span>(</span>r"(\d+)"</span>)</span>.</span>expect</span>(</span>"failed to compile static regex that was known at design time"</span>)</span></span> });</span></span> </span> let</span> haystack</span> =</span> "There are 20 bad apples in the batch of 100"</span>;</span></span> let</span> captures_iter</span> =</span> re</span>.</span>captures_iter</span>(haystack);</span></span> for</span> captures</span> in</span> captures_iter {</span></span> let</span> number</span> =</span> captures</span></span> .</span>get</span>(</span>1</span>)</span></span> .</span>with_context</span>(</span>\|\|</span> format!</span>(</span>"failed to extract number from: {haystack:?}"</span>))</span>?</span></span> .</span>as_str</span>();</span></span> println!</span>(</span>"A number {number} was found in {haystack:?}"</span>);</span></span> }</span></span> </span> // Prints:</span></span> // A number 20 was found in "There are 20 bad apples in the batch of 100"</span></span> // A number 100 was found in "There are 20 bad apples in the batch of 100"</span></span> </span> Ok</span>(())</span></span> }</span></span></code></pre> Crate Tracing Subscriber 2024-11-24T00:00:00+00:00 Crate Docs</a></h1> https://docs.rs/tracing-subscriber/latest/tracing_subscriber/</a></p> Example initialization</a></h1> Other examples available here</a></p> Requires features: env-filter</code> and std</code></p> use</span> tracing_subscriber</span>::</span>{</span></span> fmt</span>::</span>{</span>self</span>,</span> format</span>::</span>FmtSpan</span>},</span></span> prelude</span>::*</span>,</span></span> EnvFilter</span>,</span></span> };</span></span> </span> tracing_subscriber</span>::</span>registry</span>()</span></span> .</span>with</span>(</span>fmt</span>::</span>layer</span>()</span>.</span>with_span_events</span>(</span>FmtSpan</span>::</span>ACTIVE</span>))</span></span> .</span>with</span>(</span>EnvFilter</span>::</span>try_from_default_env</span>()</span>.</span>unwrap_or_else</span>(</span>\|</span>_</span>\|</span> {</span></span> EnvFilter</span>::</span>new</span>(</span>if</span> cfg!</span>(debug_assertions) {</span></span> "zbus=warn,info"</span></span> }</span> else</span> {</span></span> "warn"</span></span> })</span></span> }))</span></span> .</span>init</span>();</span></span></code></pre> Redirect Output 2024-11-13T00:00:00+00:00 stderr to stdout</a></h1> Use 2>&1</code></p> In the example without the redirect there is no output in vscode because tar</code> requires arguments and instead prints to stderr</code></p> tar</span> 2>&1 \|</span> code</span> -</span></span></code></pre> If sending to a file instead of piping stdout</code> then redirect stdout</code> first (the order the redirects are done in matters). As it does the redirects from left to right as per SA Question</a>. (See excerpt below)</p> cmd >>file.txt 2>&1</code> Bash executes the redirects from left to right as follows:</p> >>file.txt</code>: Open file.txt in append mode and redirect stdout there.</li> 2>&1</code>: Redirect stderr to “where stdout is currently going”. In this case, that is a file opened in append mode. In other words, the &1 reuses the file descriptor which stdout currently uses.</li> </ol> </blockquote> tar</span> >></span>file.txt</span> 2>&1</span></span></code></pre> QR Codes 2024-11-01T00:00:00+00:00 My personal website (This site)</a></h1> https://chester.wykies.com</a></p> </a></p> LinkedIn</a></h1> https://www.linkedin.com/in/cwyke</a></p> </a></p> GitHub</a></h1> https://github.com/c-git/</a></p> </a></p> Using included apps on your phone to create QR Codes</a></h1> This was tested on a Samsung Android phone. Not sure how well this generalizes.</p> Go to the phone app</li> Go to the contacts tab</li> Find the contact you want to create the QR Code for (add them and come back if you don’t have them saved, eg. create a contact for yourself for the info you want to share)</li> Tap on the contact to bring up the options </li> Select the “i” option to open the contact details</li> Use the three dots labelled More</code> to open the context menu</li> Select QR code</code></li> Use the Share</code> button to do with it what seems good to you</li> </ol> Decoding QR codes</a></h1> I was fortunate to notice a very cool rust crate in This Week In Rust</a>. It’s called zedbar</a> and is:</p> a webpage</a> running wasm that you can drag and drop images onto</li> a library that can be included in your rust</a> or Node.js</a> project (via WASM)</li> a CLI that you can install using cargo</code></li> </ul> cargo</span> install zedbar</span></span></code></pre> See sample output from the CLI below on the QR code for my website</p> $</span> zedbarimg qr_code_personal_site.png</span></span> QrCode:https://chester.wykies.com/</span></span> scanned</span> 1</span> barcode symbols from</span> 1</span> image</span>(</span>s</span>)</span></span></code></pre> Presentation Animation Removal 2024-10-09T00:00:00+00:00 I prefer create slides with animations to help the viewers follow the part of the slide I’m referring to. However, if you need a PDF version without animations then it becomes necessary to remove split the slides with animations into multiple slides. The following is the sequence of steps I used to do this as it takes a lot of the concentration out of the process making it more bearable.</p>

Divine Mercy Chaplet

2026-03-03T00:00:00+00:00

After I copied the bellow from the app to make it easier to access I found that the Marian Fathers already have a website with more information and laid out much better than I have. I’ll keep this page as I already typed it up but I would deferrer any visitors to the divine mercy website</a> or see links to parts I found helpful to get started as it may feel a bit overwhelming to start off:

The message</a> </li>
The chaplet</a> and the step by step</a> instructions </li>
Novena</a> </li>
Pray along with Video</a> Really moving The Chaplet of Divine Mercy in Song (Complete)</a>.
</iframe> </div> </li> </ul>
Lyrics, and prayer versions used in video</summary>
Show Optional Opening Prayer</summary>
You expired, Jesus,
but the source of life gushed forth for souls,
and the ocean of mercy opened up for the whole world.
O Fount of Life, unfathomable Divine Mercy,
envelop the whole world and empty Yourself out upon us.
O Blood and Water,
which gushed forth from the Heart of Jesus as a fount of mercy for us,
I trust in You! (3x) </details>

Lyrics to opening hymn
Hail to Thee! True body sprung
From the Virgin Mary’s womb!
Same that on the cross was hung
Bore for man the bitter doom.
Sweet Jesus, Mary’s son.
Thou whose side was pierced and flowed
Both with water and with blood;
Suffer us to taste of Thee
In our life’s last agony.
Sweet Jesus, Mary’s son. </li>

The Apostle’s Creed (version said in the video)
I believe in God,
the Father almighty,
Creator of Heaven and earth,
I believe in Jesus Christ,
His only Son, our Lord,
He was conceived by the power of the Holy Spirit,
and born of the Virgin Mary,
He suffered under Pontius Pilate,
was crucified, died, and was buried;
He descended to the dead;
on the third day He rose again;
He ascended into Heaven,
and is seated at the right hand of the Father.
He will come again to judge the living and the dead.
I believe in the Holy Spirit, the holy catholic Church,
the communion of Saints,
the forgiveness of sins,
the resurrection of the body,
and the life everlasting. Amen. </li>

Closing Song
Holy God, Holy Mighty One, Holy Immortal One, have mercy on us and on the whole world. (x3) </li>

Closing prayer (Not included in video)
Eternal God, in whom mercy is endless,
and the treasury of compassion inexhaustible,
look kindly upon us,
and increase Your mercy in us,
that in difficult moments,
we might not despair, nor become despondent,
but with great confidence, submit ourselves to Your holy will,
which is Love and Mercy Itself. Amen. </li> </ul> </details>
Source: Divine Mercy</a> App

Start with the sign of the cross </li>

On the first big bead

Show Optional Opening Prayer</summary>
You expired, Jesus,
but the source of life gushed forth for souls,
and the ocean of mercy opened up for the whole world.
O Fount of Life, unfathomable Divine Mercy,
envelop the whole world and empty Yourself out upon us.
O Blood and Water,
which gushed forth from the Heart of Jesus as a fount of mercy for us,
I trust in You! (3x) </li> </ul> </details>

On the three small beads say

Pray an Our Father</li> </ol>

Show words</summary>
Our Father, who art in Heaven,
hallowed by Thy Name;
Thy kingdom come;
Thy will be done on earth
as it is in Heaven.
Give us this day
our daily bread;
and forgive us our trespasses
as we forgive those who trespass against us;
and lead us not into temptation,
but deliver us from evil. Amen. </details> </li>

Pray a Hail Mary</li> </ol>

Show words</summary>
Hail Mary, full of grace.
The Lord is with thee.
Blessed art thou among women,
and blessed is the fruit of thy womb, Jesus.
Holy Mary, Mother of God,
pray for us sinners,
now and at the hour of our death. Amen </details> </li>

Pray The Apostle’s Creed</li> </ol>

Show words</summary>
I believe in God,
the Father almighty,
Creator of Heaven and earth,
and in Jesus Christ,
His only Son, our Lord,
who was conceived by the Holy Spirit,
born of the Virgin Mary,
suffered under Pontius Pilate,
was crucified, died, and was buried;
He descended into hell;
on the third day He rose again from the dead;
He ascended into Heaven,
and is seated at the right hand of God the Father almighty;
from there He will come to judge the living and the dead.
I believe in the Holy Spirit, the holy catholic Church,
the communion of Saints,
the forgiveness of sins,
the resurrection of the body,
and life everlasting. Amen. </details> </li> </ul> </li>

On each of the remaining large beads pray:
The Eternal Father
Eternal Father,
I offer You the Body and Blood,
Soul and Divinity
of Your dearly beloved Son,
Our Lord Jesus Christ,
in atonement for our sins and those of the whole world. </li>

On each of the remaining small beads pray:
For the sake of His sorrowful Passion,
have mercy on us and on the whole world. </li>

Closing Prayers
Holy God, Holy Mighty One, Holy Immortal One, have mercy on us and on the whole world. (x3)
Eternal God, in whom mercy is endless,
and the treasury of compassion inexhaustible,
look kindly upon us,
and increase Your mercy in us,
that in difficult moments,
we might not despair, nor become despondent,
but with great confidence, submit ourselves to Your holy will,
which is Love and Mercy Itself. Amen. </li>

End with the sign of the cross. </li> </ul>

Image credit the https://www.thedivinemercy.org/</a> page on: The Image of The Divine Mercy</a>

Leetcode

2025-03-24T00:00:00+00:00

I quite enjoy doing leetcode as small contained puzzles that are easy to verify. It’s also pretty good for trying out a new language in some regards. This page is a collection of resources for various purposes:

Problem solving tips and notes</a></h1>
This is a list of tips I want to remember. It’s likely that there is a more comprehensive list somewhere but I haven’t looked for it. There are just small techniques to apply. Not really a full pattern but just a way to reframe problems. If you know of a comprehensive list of techniques like these please tell me about it. I’ll check it out and link to it if I find it good. I included an example problem where the technique applies.
Try brute force</a></h2>

437. Path Sum III</a></li> </ul>
Coding up brute force is a good starting point but a better starting point is just typing out or writing up what you need to keep track of to solve it as a human. Add “digital” constraints like only looking at one variable at a time and then try to solve and see where you have repeated work and things like that which could cause the optimal solution to fall out. In the example problem once I looked at Deepti</a> manually solve it, the solution became obvious and I wasn’t stuck anymore.

424. Longest Repeating Character Replacement</a></li> </ul>
Also note where information you track gets used. Is this example, Neetcode</a> was able to drop the constant 26 in the `O(26n)</code> down to 1 by tracking the max frequency. This works (also explained in the video) because the only time we can increase the result is when we find a new max. Before that it really doesn’t matter, so having a max that is too high does not have negative side effects. </details>`
Tips for detecting DP</a></h2> 139. Word Break</a></li> </ul> I eventually solved the problem by patterning on Deepti’s solution</a>. What I think I missed is that even though because of how the question is constructed the ways must be tried, brute force even with a trie would be too slow as it’s exponential. Lesson: If the ways really must be tried and trying them is exponential, it’s likely a dynamic programming (DP) problem. </details> Rearrange formulas (especially if modulus is involved - think of operations closed under modulus (+,-,))</a></h2> Source: Taken from Hint #2 for problem. 2364. Count Number of Bad Pairs</a></li> 2845. Count of Interesting Subarrays</a></li> </ul> Check to see if formulas in question can be rearranged into one that is easier to optimize for Notice that (j - i != nums[j] - nums[i]) is the same as (nums[i] - i != nums[j] - j). </blockquote> </details> Consider partition_point</code></a></h2> Inspired by: https://www.youtube.com/watch?v=TjthKf7Mc_8</a> 33. Search in Rotated Sorted Array</a></li> 34. Find First and Last Position of Element in Sorted Array</a></li> 704. Binary Search</a></li> </ul> When you need binary search consider using partition_point</code> function from rust std</a>. If it’s not allowed manually implement as below. /// Returns the index of the partition point according to the given predicate (the index of the first element of the second partition). /// See <https://doc.rust-lang.org/std/primitive.slice.html#method.partition_point> for more info fn partition_point<T>(arr: &[T], is_left_half: impl Fn(&T) -> bool) -> usize { let mut size = arr.len(); if size == 0 { return 0; } let mut base = 0usize; while size > 1 { let half = size / 2; let mid = base + half; base = if is_left_half(&arr[mid]) { mid } else { base }; size -= half; } if is_left_half(&arr[base]) { base + 1 } else { base } }</code></pre></details> Be comfortable with permutations</a></h2> 46. Permutations</a></li> </ul> Sometimes brute force is what the question wants. I prefer Heap’s Algorithm</a> but it’s too difficult to memorize. So instead I think the iterative solution from the video is the easiest to remember without feeling too icky /// Based on https://www.youtube.com/watch?v=FZe0UqISmUw pub fn permute(nums: Vec<i32>) -> Vec<Vec<i32>> { let mut result = vec![vec![]]; // For each number insert it into each position in the previous solutions // Including at the end for num in nums { let mut new_result = vec![]; for prev_result_val in result { for i in 0..=prev_result_val.len() { let mut clone = prev_result_val.clone(); clone.insert(i, num); new_result.push(clone); } } result = new_result; } result }</code></pre></details> Be comfortable with subsets</a></h2> 78. Subsets</a></li> </ul> Note that this is not subarrays. Similarly to permutations</a> an iterative approach can be used to just add all numbers to the end only instead of all positions like permutations. pub fn subsets(nums: Vec<i32>) -> Vec<Vec<i32>> { // Based on editorial and https://www.youtube.com/watch?v=z3xEwMA5Rn8 let mut result = vec![vec![]]; for num in nums { let n = result.len(); for i in 0..n { let mut next = result[i].clone(); next.push(num); result.push(next); } } result }</code></pre></details> Interview Preparation</a></h1> In my opinion if you already have experience with leetcode then a good video to start with is this one</a> from Uncle Steve</a> where he starts of with summarizing the article How well do LeetCode ratings predict interview performance? Here’s the data</a>. List of problems from the description of the video</summary> Top ‘Secretly Easy’ Hard Problems: #1: Reverse Nodes in k-Group</a> - Score: 0.034 #2: Median of Two Sorted Arrays</a> - Score: 0.0298 #3: N-Queens II</a> - Score: 0.0288 #4: N-Queens</a> - Score: 0.0255 #5: Robot Room Cleaner</a> - Score: 0.0192 Top ‘Most Efficient for Interview Prep’ Hard Problems: #1: Longest Increasing Path in a Matrix</a> - Score: 1.8094 #2: Trapping Rain Water</a> - Score: 1.6964 #3: The Skyline Problem</a> - Score: 1.5794 #4: Word Break II</a> - Score: 1.5601 #5: Smallest Range Covering Elements from K Lists</a> - Score: 1.1687 Hardest Questions Actually Used in FAANG Interviews: #1: Partition Array Into Two Arrays to Minimize Sum Difference</a> - Score: 12.3924 #2: Regular Expression Matching</a> - Score: 12.1070 #3: Reverse Pairs</a> - Score: 9.0915 #4: Median of Two Sorted Arrays</a> - Score: 8.2952 #5: Max Points on a Line</a> - Score: 8.0952 </blockquote> </details> If you’re new to leetcode then start with neetcode</a> it makes it easy to find a path to follow. My key takeaway is that “reasonable” hard problems are actually not hard just require multiple techniques and thus you get more value from doing them. But be warned some of the hard problems (the one’s I don’t generally consider reasonable) just require niche knowledge. The following are some lists I think are worth taking a look at and why. When starting off getting practice on different techniques for developing solutions is good to help you build up intuition on when a particular technique is appropriate. However, once you are comfortable with the techniques then not having a hint on which technique to use is better to help you practice identifying the technique(s) you should use. Short List from Neetcode </summary> Source: https://www.linkedin.com/posts/navdeep-singh-3aaa14161_if-i-only-had-a-short-time-to-study-for-my-activity-7312473774598012928-ZhXz</a> If I only had a short time to study for my coding interview, these are the 15 questions I would solve (in order) </blockquote> 🟢 Two Sum</a> (Leetcode</a>) - Practice using hash maps.</li> 🟡 Product of Array Except Self</a> (Leetcode</a>) Practice prefix / suffix sums.</li> 🟡 3Sum</a> (Leetcode</a>) - Practice sorting and two pointers.</li> 🟡 Longest Repeating Character Replacement</a> (Leetcode</a>) - Practice sliding window.</li> 🟡 Daily Temperatures</a> (Leetcode</a>) - Practice monotonic stack.</li> 🟡 Search in Rotated Sorted Array</a> (Leetcode</a>) - Practice Binary Search on array.</li> 🟡 Koko Eating Bananas</a> (Leetcode</a>) - Practice Binary Search on a range of values, rather then a data structure.</li> 🟡 LRU Cache</a> (Leetcode</a>) - Practice doubly linked lists and hashmaps.</li> 🟢 Same Binary Tree</a> (Leetcode</a>) - Practice tree traversal - DFS or BFS.</li> 🔴 Serialize and Deserialize Binary Tree</a> (Leetcode</a>) - Practice hard tree traversal.</li> 🔴 Median in Data Stream</a> (Leetcode</a>) - Practice two heaps pattern.</li> 🟡 Combination Sum</a> (Leetcode</a>) - Practice two-branch backtracking.</li> 🟡 Course Schedule</a> (Leetcode</a>) - Practice DFS or BFS on adjacency list.</li> 🟡 Rotting Oranges</a> (Leetcode</a>) - Practice multi-source BFS.</li> 🟡 Longest Common Subsequence</a> (Leetcode</a>) - Practice dynamic programming, top-down or bottom-up.</li> </ol> </details> These are some good videos to help you get oriented: The LeetCode Fallacy</a> by NeetCode</a></li> How to Start LeetCode from ZERO in 2025</a> by AlgoMaster</a></li> </ul> List</th> Reason</th> Organization</th></tr></thead> NeetCode Roadmap</a></td> Provides a guided tree to follow based on prerequisites</td> Tree with solution types</td></tr> LeetCode 75</a></td> Provided by leetcode and free (they also have list available to premium users, support them if you’re able)</td> Grouped by Solution Type</td></tr> AlgoMaster</a></td> Has links to an explanation for each solution type before the problems. Has links to solutions for each problem (seems like his) and preloaded search for solutions on YouTube</td> Grouped by Solution Type</td></tr> Grind 75 by author of Blind 75</a></td> Allows customization of plan to the amount of time you have available and can not show what topic is covered by a question for you to practice that skill</td> Customizable</td></tr> </tbody></table> Recreational</a></h1> If you’re objective is just practice or for fun then working locally can be less annoying than working in the text editor provided. Also if you want to get practice with using your IDE of choice and learning from the autocomplete and docs displayed in the IDE. Then I recommend cargo-leet</a>. It’s a pretty basic download tool that just tries to setup the tests from the description for you. Happy to accept contributions if you’re so included. Google APIs 2025-03-20T00:00:00+00:00 Google Sheets</a></h1> Foreword</a></h2> It’s been a journey trying to decide what would be the most sustainable way to interact with Google’s API for “Google Sheets”. Seems that currently Google is currently developing a client library</a> for rust but it isn’t done yet. My current use case isn’t amenable to a still experimental API thus I decided to use the next best one. Byron</a> setup a repo</a> to generate clients based on Google’s discovery service. He really did a very good job with it and it seems to at present be the best option. I also considered one</a> created by the Oxide Computer Company</a> but decided to use the one Byron created as his also came with a CLI that I could use to better understand how to use it. Using google_sheets4</a></a></h2> Sources: Medium Article</a> by Chris Grounds</li> Auto generated CLI</a> created by Byron</li> </ul> WIP The project I was going to use this on has been paused but already started the notes so saving them. lettre 2025-03-15T00:00:00+00:00 Sending email using smtp and Gmail</a></h1> They have a pretty clear example</a> on in their crate. I’d just add that you should ensure you have 2 factor authentication enabled and then that will allow you to create an APP password that you can use for this purpose. You’ll also need to enable POP in settings. Delete Old Files Automatically 2025-02-28T00:00:00+00:00 Explanation</a></h1> Source: https://stackoverflow.com/questions/45838304/bash-delete-files-older-than-3-months</a> Before you actually run the delete command it might be good to use -print</code> as below to see what will be deleted. In both commands (the print and delete one): PATH</code> should be replaced with the path to the folder you want to do the deletes in.</li> DAYS</code> should be replaced with the number of days you need.</li> </ul> See also cron</a> for automating the command Preview output via print</a></h1> Format: find PATH -mtime DAYS -type f -print</code></pre> Example find . -mtime +90 -type f -print</code></pre>Actual delete command</a></h1> find PATH -mtime DAYS -type f -delete</code></pre> Macros 2025-02-24T00:00:00+00:00 Info Sources</a></h1> Rust Book</a> Declarative Macros with macro_rules! for General Metaprogramming</a> - Explained example of a macro</li> </ul> </li> Rust by Example</a></li> Rust Reference</a> Syntax</a> Designators</a> - Types of designators available (Macro Variable types)</li> </ul> </li> </ul> </li> </ul> Motivation to finally try macros</a></h1> Exercism - Space Age</a></li> </ul> Omit From History 2025-02-20T00:00:00+00:00 Source: https://stackoverflow.com/questions/6475524/how-do-i-prevent-commands-from-showing-up-in-bash-history</a> If you want to leave commands out of the history prefix them with whitespace. Enum Conversion 2025-01-19T00:00:00+00:00 Switching back and forth between an Enum and u8</a></h1> Sources: https://stackoverflow.com/a/76785380</a></li> https://stackoverflow.com/a/76299020</a></li> </ul> #!/usr/bin/env -S cargo +nightly -Zscript ---cargo package.edition = "2021" # Desirable to stop warning but not needed [dependencies] strum = { version = "0.26.3", features = ["derive"] } --- use strum::FromRepr; #[derive(FromRepr, Debug, PartialEq)] #[repr(u8)] enum MyEnum { A = 1, B, C, } fn main() { // u8 to Enum let x = MyEnum::from_repr(2); assert_eq!(x, Some(MyEnum::B)); // Enum to u8 let x = MyEnum::C as u8; assert_eq!(x, 3); }</code></pre> vscode 2025-01-04T00:00:00+00:00 In all headings RA means RustAnalyzer Setting features for RA</a></h1> In .vscode/settings.json</code> add: // .vscode/settings.json { "rust-analyzer.cargo.features": ["FEATURE1_HERE", "FEATURE2_HERE"], }</code></pre>Setting target for RA</a></h1> See the example for wasm</a> Disable default features for RA</a></h1> // .vscode/settings.json { "rust-analyzer.cargo.noDefaultFeatures": true }</code></pre> Wayland or x11? 2024-12-23T00:00:00+00:00 How to know which you are using</a></h1> Source: https://unix.stackexchange.com/questions/202891/how-to-know-whether-wayland-or-x11-is-being-used</a> Based on an error message</a> in the rust winit crate I think the easiest way to check is see if either of the environment variables WAYLAND_DISPLAY</code> or WAYLAND_SOCKET</code> is set. And the environment variable DISPLAY</code> should be set if you are on x11. So… You get output on at least one of this if you are on Wayland: echo $WAYLAND_DISPLAY echo $WAYLAND_SOCKET</code></pre> And you should get output on this if you are on x11: echo $DISPLAY</code></pre> The actual instruction from the site are to run loginctl</code></pre> Then take the value under session in the first column and insert into <SESSION></code> in the next command loginctl show-session <SESSION> -p Type</code></pre> Github Actions 2024-12-23T00:00:00+00:00 Reusing a github action</a></h1> Source: https://docs.github.com/en/actions/sharing-automations/reusing-workflows#calling-a-reusable-workflow</a> See source for more details but I’ll focus on the use case I most commonly have, two workflows in the same repo and I want to call one from the other to ensure it runs and succeeds before the other one starts. Example use case can be found at https://github.com/wykies/crates/</a> where the shuttle.yml</code> calls general.yml</code>. In the workflow being called you must have the following in inside of the on</code> section. on: workflow_call:</code></pre> and in the caller you need to have a separate job that put the relative path the called workflow in uses as below: jobs: run_tests: uses: ./.github/workflows/general.yml deploy: runs-on: ubuntu-latest needs: run_tests # Requires that the other job succeeds before this one will start steps:</code></pre> Regex 2024-12-02T00:00:00+00:00 Capture first match</a></h1> NB: If regex is not executed more than once then you may opt to not use the Cells but they remove the need to recompile the regex. Dependencies (anyhow</code> is not needed by makes the code cleaner) cargo add regex cargo add anyhow</code></pre>use anyhow::Context as _; use regex::Regex; use std::sync::OnceLock; fn main() -> anyhow::Result<()> { static CELL: OnceLock<Regex> = OnceLock::new(); let re = CELL.get_or_init(|| { Regex::new(r"(\d+)").expect("failed to compile static regex that was known at design time") }); let haystack = "There are 20 bad apples in the batch of 100"; let captures = re .captures(haystack) .with_context(|| format!("failed to find a match in: {haystack:?}"))?; let number = captures .get(1) .with_context(|| format!("failed to extract number from: {haystack:?}"))? .as_str(); // Prints: The number 20 was found in "There are 20 bad apples in the batch of 100" println!("The number {number} was found in {haystack:?}"); Ok(()) }</code></pre>Capture all matches</a></h1> See notes on Capture first match</a> cargo add regex cargo add anyhow</code></pre>use anyhow::Context as _; use regex::Regex; use std::sync::OnceLock; fn main() -> anyhow::Result<()> { static CELL: OnceLock<Regex> = OnceLock::new(); let re = CELL.get_or_init(|| { Regex::new(r"(\d+)").expect("failed to compile static regex that was known at design time") }); let haystack = "There are 20 bad apples in the batch of 100"; let captures_iter = re.captures_iter(haystack); for captures in captures_iter { let number = captures .get(1) .with_context(|| format!("failed to extract number from: {haystack:?}"))? .as_str(); println!("A number {number} was found in {haystack:?}"); } // Prints: // A number 20 was found in "There are 20 bad apples in the batch of 100" // A number 100 was found in "There are 20 bad apples in the batch of 100" Ok(()) }</code></pre> Crate Tracing Subscriber 2024-11-24T00:00:00+00:00 Crate Docs</a></h1> https://docs.rs/tracing-subscriber/latest/tracing_subscriber/</a> Example initialization</a></h1> Other examples available here</a> Requires features: env-filter</code> and std</code> use tracing_subscriber::{ fmt::{self, format::FmtSpan}, prelude::, EnvFilter, }; tracing_subscriber::registry() .with(fmt::layer().with_span_events(FmtSpan::ACTIVE)) .with(EnvFilter::try_from_default_env().unwrap_or_else(|_| { EnvFilter::new(if cfg!(debug_assertions) { "zbus=warn,info" } else { "warn" }) })) .init();</code></pre> Redirect Output 2024-11-13T00:00:00+00:00 stderr to stdout</a></h1> Use 2>&1</code> In the example without the redirect there is no output in vscode because tar</code> requires arguments and instead prints to stderr</code> tar 2>&1 | code -</code></pre> If sending to a file instead of piping stdout</code> then redirect stdout</code> first (the order the redirects are done in matters). As it does the redirects from left to right as per SA Question</a>. (See excerpt below) cmd >>file.txt 2>&1</code> Bash executes the redirects from left to right as follows: >>file.txt</code>: Open file.txt in append mode and redirect stdout there.</li> 2>&1</code>: Redirect stderr to “where stdout is currently going”. In this case, that is a file opened in append mode. In other words, the &1 reuses the file descriptor which stdout currently uses.</li> </ol> </blockquote> tar >>file.txt 2>&1</code></pre> QR Codes 2024-11-01T00:00:00+00:00 My personal website (This site)</a></h1> https://chester.wykies.com</a> </a> LinkedIn</a></h1> https://www.linkedin.com/in/cwyke</a> </a> GitHub</a></h1> https://github.com/c-git/</a> </a> Using included apps on your phone to create QR Codes</a></h1> This was tested on a Samsung Android phone. Not sure how well this generalizes. Go to the phone app</li> Go to the contacts tab</li> Find the contact you want to create the QR Code for (add them and come back if you don’t have them saved, eg. create a contact for yourself for the info you want to share)</li> Tap on the contact to bring up the options </li> Select the “i” option to open the contact details</li> Use the three dots labelled More</code> to open the context menu</li> Select QR code</code></li> Use the Share</code> button to do with it what seems good to you</li> </ol> Decoding QR codes</a></h1> I was fortunate to notice a very cool rust crate in This Week In Rust</a>. It’s called zedbar</a> and is: a webpage</a> running wasm that you can drag and drop images onto</li> a library that can be included in your rust</a> or Node.js</a> project (via WASM)</li> a CLI that you can install using cargo</code></li> </ul> cargo install zedbar</code></pre> See sample output from the CLI below on the QR code for my website $ zedbarimg qr_code_personal_site.png QrCode:https://chester.wykies.com/ scanned 1 barcode symbols from 1 image(s)</code></pre> Presentation Animation Removal 2024-10-09T00:00:00+00:00 I prefer create slides with animations to help the viewers follow the part of the slide I’m referring to. However, if you need a PDF version without animations then it becomes necessary to remove split the slides with animations into multiple slides. The following is the sequence of steps I used to do this as it takes a lot of the concentration out of the process making it more bearable.

Chester Wyke

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