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I was drawn to programming, science, technology and science fiction
ever since I was a little kid. I can't say it's because I wanted to
make the world a better place. Not really. I was simply drawn to it
because I was drawn to it. Writing programs was fun. Figuring out how
nature works was fascinating. Science fiction felt like a grand
adventure.
Then I started a software company and poured every ounce of energy
into it. It failed. That hurt, but that part is ok. I made a lot of
mistakes and learned from them. This experience made me much, much
@xsot
xsot / instructions.md
Last active March 3, 2024 13:42
sed maze solver

Usage

sed -E -f solver.sed input where input is a file containing the maze.

For best results, resize your terminal to match the height of the maze. To disable animations, delete the lines containing p.

Maze format

The solver assumes the following:

  • The maze only contains the characters # \nSE
  • Every line has the same number of characters
  • There is only one start (S) and end (E)
@paulirish
paulirish / what-forces-layout.md
Last active November 19, 2024 08:58
What forces layout/reflow. The comprehensive list.

What forces layout / reflow

All of the below properties or methods, when requested/called in JavaScript, will trigger the browser to synchronously calculate the style and layout*. This is also called reflow or layout thrashing, and is common performance bottleneck.

Generally, all APIs that synchronously provide layout metrics will trigger forced reflow / layout. Read on for additional cases and details.

Element APIs

Getting box metrics
  • elem.offsetLeft, elem.offsetTop, elem.offsetWidth, elem.offsetHeight, elem.offsetParent
@karpathy
karpathy / min-char-rnn.py
Last active November 19, 2024 10:40
Minimal character-level language model with a Vanilla Recurrent Neural Network, in Python/numpy
"""
Minimal character-level Vanilla RNN model. Written by Andrej Karpathy (@karpathy)
BSD License
"""
import numpy as np
# data I/O
data = open('input.txt', 'r').read() # should be simple plain text file
chars = list(set(data))
data_size, vocab_size = len(data), len(chars)
[
{ "name": "Shanghai", "lat": 31.22222, "lng": 121.45806 },
{ "name": "Buenos Aires", "lat": -34.61315, "lng": -58.37723 },
{ "name": "Mumbai", "lat": 19.07283, "lng": 72.88261 },
{ "name": "Mexico City", "lat": 19.42847, "lng": -99.12766 },
{ "name": "Beijing", "lat": 39.9075, "lng": 116.39723 },
{ "name": "Karachi", "lat": 24.9056, "lng": 67.0822 },
{ "name": "Istanbul", "lat": 41.01384, "lng": 28.94966 },
{ "name": "Tianjin", "lat": 39.14222, "lng": 117.17667 },
{ "name": "Guangzhou", "lat": 23.11667, "lng": 113.25 },
@john2x
john2x / 00_destructuring.md
Last active August 23, 2024 07:45
Clojure Destructuring Tutorial and Cheat Sheet

Clojure Destructuring Tutorial and Cheat Sheet

(Related blog post)

Simply put, destructuring in Clojure is a way extract values from a datastructure and bind them to symbols, without having to explicitly traverse the datstructure. It allows for elegant and concise Clojure code.

Vectors and Sequences

@aras-p
aras-p / preprocessor_fun.h
Last active November 15, 2024 09:22
Things to commit just before leaving your job
// Just before switching jobs:
// Add one of these.
// Preferably into the same commit where you do a large merge.
//
// This started as a tweet with a joke of "C++ pro-tip: #define private public",
// and then it quickly escalated into more and more evil suggestions.
// I've tried to capture interesting suggestions here.
//
// Contributors: @r2d2rigo, @joeldevahl, @msinilo, @_Humus_,
// @YuriyODonnell, @rygorous, @cmuratori, @mike_acton, @grumpygiant,
@hellerbarde
hellerbarde / latency.markdown
Created May 31, 2012 13:16 — forked from jboner/latency.txt
Latency numbers every programmer should know

Latency numbers every programmer should know

L1 cache reference ......................... 0.5 ns
Branch mispredict ............................ 5 ns
L2 cache reference ........................... 7 ns
Mutex lock/unlock ........................... 25 ns
Main memory reference ...................... 100 ns             
Compress 1K bytes with Zippy ............. 3,000 ns  =   3 µs
Send 2K bytes over 1 Gbps network ....... 20,000 ns  =  20 µs
SSD random read ........................ 150,000 ns  = 150 µs

Read 1 MB sequentially from memory ..... 250,000 ns = 250 µs

@jboner
jboner / latency.txt
Last active November 19, 2024 14:58
Latency Numbers Every Programmer Should Know
Latency Comparison Numbers (~2012)
----------------------------------
L1 cache reference 0.5 ns
Branch mispredict 5 ns
L2 cache reference 7 ns 14x L1 cache
Mutex lock/unlock 25 ns
Main memory reference 100 ns 20x L2 cache, 200x L1 cache
Compress 1K bytes with Zippy 3,000 ns 3 us
Send 1K bytes over 1 Gbps network 10,000 ns 10 us
Read 4K randomly from SSD* 150,000 ns 150 us ~1GB/sec SSD