William Chan wc2184

The Go language for experienced programmers

Why use Go?

Like C, but with garbage collection, memory safety, and special mechanisms for concurrency
Pointers but no pointer arithmetic
No header files
Simple, clean syntax
Very fast native compilation (about as quick to edit code and restart as a dynamic language)
Easy-to-distribute executables

Copy-to-clipboard Bookmarklet

Create Bookmarklet (browser bookmark that executes Javsacript) to copy a given text to Clipboard.

This is the base javascript:

(function (text) {
  var node = document.createElement('textarea')
  var selection = document.getSelection()

System Design Cheatsheet

Picking the right architecture = Picking the right battles + Managing trade-offs

Basic Steps

Clarify and agree on the scope of the system

User cases (description of sequences of events that, taken together, lead to a system doing something useful)
- Who is going to use it?
- How are they going to use it?

Meaning of amortized

I feel like I have a vague understanding of what an amortized analysis is. From what I've noticed, it's the time if the action in consideration is done a large number of times (on a large data set?). I know it's in contrast to worst-case cost analysis but if anyone has any helpful ways to explain it and how to find amortized cost, that would be great.

Instructor. 15h

You can think of amortized a little like "average", but there's a subtle difference.

Average involves a random process. Amortized does not.

"A little bit of slope makes up for a lot of y-intercept"

01/13/2012. From a lecture by Professor John Ousterhout at Stanford, class CS140

Here's today's thought for the weekend. A little bit of slope makes up for a lot of Y-intercept.

[Laughter]

Rails naming conventions

General Ruby conventions

Class names are CamelCase.

Methods and variables are snake_case.

Methods with a ? suffix will return a boolean.

#puts vs. print vs. p ###The 'puts' (short for "put string") and 'print' commands are both used to display the results of evaluating Ruby code. ###Both 'puts' and 'print' call the 'to_s' method on the object AND return nil.

###The primary difference between them is that 'puts' adds a newline after executing, and 'print' does not. ###They don't RETURN anything so the RETURN value is nil. ###Using 'p' calls the 'inspect' method on the object.

print "Milan"
Milan => nil

Stevey's Google Platforms Rant

I was at Amazon for about six and a half years, and now I've been at Google for that long. One thing that struck me immediately about the two companies -- an impression that has been reinforced almost daily -- is that Amazon does everything wrong, and Google does everything right. Sure, it's a sweeping generalization, but a surprisingly accurate one. It's pretty crazy. There are probably a hundred or even two hundred different ways you can compare the two companies, and Google is superior in all but three of them, if I recall correctly. I actually did a spreadsheet at one point but Legal wouldn't let me show it to anyone, even though recruiting loved it.

I mean, just to give you a very brief taste: Amazon's recruiting process is fundamentally flawed by having teams hire for themselves, so their hiring bar is incredibly inconsistent across teams, despite various efforts they've made to level it out. And their operations are a mess; they don't real

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	var $ = document.querySelector.bind(document);
	// return array of selected elements - $$('img.dog')
	var $$ = document.querySelectorAll.bind(document);

	// Credit: https://twitter.com/wesbos/status/608341616173182977

	<?php
	// words are there
	// http://www.infochimps.com/datasets/word-list-100000-official-crossword-words-excel-readable/downloads/144625
	$handle = @fopen("words.txt", "r");
	if ($handle) {
	while (($buffer = fgets($handle, 4096)) !== false) {
	$w = str_split(rtrim($buffer));
	$sum = 0;
	foreach ($w as $letter) {
	$sum += (ord($letter)-96);