Ciro Santilli fantasizes that he is more compassionate than average.
He feels that this manifests itself notably through his desire/ability to create amazing documentation content and notably for free.
Also related is Ciro's worry about social inequality and how to reduce it.
In school, especially before university, Ciro felt that he always treated "the ugly/unpopular" (it is horrifying that such perception of a person exists! but true) girls really well, which led some of them to like him romantically. In part this was de to Ciro Santilli's self perceived compassionate personality and enter through the narrow gate approach to life. But was also partly Ciro's fault, he should have been clearer that he was not truly interested, but he was also lonely, curious about how it was like having girlfriend, and it feels good to have someone like you. This was a sin.
He also feels like he treated working class employees (and don't forget, this is Brazil, e.g. his building janitors in São Paulo lived in the nearby favela!) with extreme equality, sometimes even better, than other richer people.
One thing Ciro does not do however is give money to beggars on the street. Those beggars do make Ciro feel extremely bad for not giving, but he feels that they must be drug addicts to be out on the street like that, and that this money would be better invested in OurBigBook.com. But maybe this is just wrong. How fucked up the world is, how far away are we from unconditional basic income???
Once Ciro was hanging out with one of his father's on a group tourist, and she was a lesbian borderline/actually activist social reform person, and she promptly gave to a beggar without batting an eye, and that made a big impression on Ciro, making him feel even worse about himself.
It must be said that at times this compassion can be a weakness see Ciro's trip to the Municipal Market of São Paulo.
Symmetric bilinear map by Ciro Santilli 37 Updated 2025-07-16
Subcase of symmetric multilinear map:
Requires the two inputs and to be in the same vector space of course.
The most important example is the dot product, which is also a positive definite symmetric bilinear form.
Iterative in-order by Ciro Santilli 37 Updated 2025-07-16
This is a bit harder than iterative pre-order: now we have to check if there is a left or right element or not:
  • (START) push current
  • if there is left:
    • move left
  • else:
    • (ELSE) pop
    • visit
    • if there is right
      • move right
      • GOTO START
    • else:
      • GOTO ELSE
The control flow can be slightly simplified if we allow NULLs: www.geeksforgeeks.org/inorder-tree-traversal-without-recursion/
Internet by Ciro Santilli 37 Updated 2025-07-16
Video 1.
Are YOU Ready for the INTERNET? by BBC (1994)
Source.
Lost Horse LLC by Ciro Santilli 37 Updated 2025-07-16
www.irishtimes.com/life-and-style/people/mackenzie-scott-how-the-former-mrs-bezos-became-a-philanthropist-like-no-other-1.4850049 MacKenzie Scott: How the former Mrs Bezos became a philanthropist like no other (2020) has some good mentions:
But as Scott's fame for giving away money has grown, so too has the deluge of appeals for gifts from strangers and old friends alike. That clamour may have driven Scott's already discreet operation further underground, with recent philanthropic announcements akin to sudden lightning bolts for unsuspecting recipients.
webpack by Ciro Santilli 37 Updated 2025-07-16
Webpack is like a magic hydra that can eat any type of file and bundle it into a single output: .js, .ts, .ccs, .scss, .jsx, .tsx, require, import, import css from .js, it doesn't matter at all, it just digests all into the same dump.
When it works, you are just left in awe and with a single Js file. When it doesn't, you're fucked and have to debug for several hours.
Demos under: webpack/. To run all of them by default:
cd webpack/min
npm install
npm run build
xdg-open index.html
To easily make changes and reload the .js output live let this run on a terminal:
npx webpack watch
Examples:
SQLite by Ciro Santilli 37 Updated 2025-07-16
The minimalism, serverlessness/lack of temporary caches/lack of permission management, Hipp's religious obsession with efficiency, the use of their own pure Fossil version control[ref]. Wait, scrap that last one. Pure beauty!
Official Git mirror: github.com/sqlite/sqlite
Create a table
sqlite3 db.sqlite3 "
CREATE TABLE 'IntegerNames' (int0 INT, char0 CHAR(16));
INSERT INTO 'IntegerNames' (int0, char0) VALUES (2, 'two'), (3, 'three'), (5, 'five'), (7, 'seven');
"
List tables:
sqlite3 db.sqlite3 '.tables'
output:
IntegerNames
Show schema of a table:
sqlite3 db.sqlite3 '.schema IntegerNames'
outputs the query that would generate that table:
CREATE TABLE IF NOT EXISTS 'IntegerNames' (int0 INT, char0 CHAR(16));
Show all data in a table:
sqlite3 db.sqlite3 'SELECT * FROM IntegerNames'
output:
2|two
3|three
5|five
7|seven
RSA (cryptosystem) by Ciro Santilli 37 Updated 2025-07-16
Based on the fact that we don't have a P algorithm for integer factorization as of 2020. But nor proof that one does not exist!
The private key is made of two randomly generated prime numbers: and . How such large primes are found: how large primes are found for RSA.
The public key is made of:
Given a plaintext message m, the encrypted ciphertext version is:
c = m^e mod n
This operation is called modular exponentiation can be calculated efficiently with the Extended Euclidean algorithm.
The inverse operation of finding the private m from the public c, e and is however believed to be a hard problem without knowing the factors of n.
However, if we know the private p and q, we can solve the problem. As follows.
First we calculate the modular multiplicative inverse. TODO continue.
The term "engine" can refer to several different concepts depending on the context. Here are a few common interpretations: 1. **Mechanical Engine**: In a mechanical context, an engine is a machine designed to convert energy into mechanical work. This includes internal combustion engines (like those found in cars) and external combustion engines (like steam engines). Engines typically convert fuel into energy through processes involving combustion, heat exchange, or mechanical motion.

Pinned article: Introduction to the OurBigBook Project

Welcome to the OurBigBook Project! Our goal is to create the perfect publishing platform for STEM subjects, and get university-level students to write the best free STEM tutorials ever.
Everyone is welcome to create an account and play with the site: ourbigbook.com/go/register. We belive that students themselves can write amazing tutorials, but teachers are welcome too. You can write about anything you want, it doesn't have to be STEM or even educational. Silly test content is very welcome and you won't be penalized in any way. Just keep it legal!
We have two killer features:
  1. topics: topics group articles by different users with the same title, e.g. here is the topic for the "Fundamental Theorem of Calculus" ourbigbook.com/go/topic/fundamental-theorem-of-calculus
    Articles of different users are sorted by upvote within each article page. This feature is a bit like:
    • a Wikipedia where each user can have their own version of each article
    • a Q&A website like Stack Overflow, where multiple people can give their views on a given topic, and the best ones are sorted by upvote. Except you don't need to wait for someone to ask first, and any topic goes, no matter how narrow or broad
    This feature makes it possible for readers to find better explanations of any topic created by other writers. And it allows writers to create an explanation in a place that readers might actually find it.
    Figure 1.
    Screenshot of the "Derivative" topic page
    . View it live at: ourbigbook.com/go/topic/derivative
  2. local editing: you can store all your personal knowledge base content locally in a plaintext markup format that can be edited locally and published either:
    This way you can be sure that even if OurBigBook.com were to go down one day (which we have no plans to do as it is quite cheap to host!), your content will still be perfectly readable as a static site.
    Figure 5. . You can also edit articles on the Web editor without installing anything locally.
    Video 3.
    Edit locally and publish demo
    . Source. This shows editing OurBigBook Markup and publishing it using the Visual Studio Code extension.
  3. https://raw.githubusercontent.com/ourbigbook/ourbigbook-media/master/feature/x/hilbert-space-arrow.png
  4. Infinitely deep tables of contents:
    Figure 6.
    Dynamic article tree with infinitely deep table of contents
    .
    Descendant pages can also show up as toplevel e.g.: ourbigbook.com/cirosantilli/chordate-subclade
All our software is open source and hosted at: github.com/ourbigbook/ourbigbook
Further documentation can be found at: docs.ourbigbook.com
Feel free to reach our to us for any help or suggestions: docs.ourbigbook.com/#contact