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Fábio Oliveira foliveira

I may be slow to respond.
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foliveira /
Created July 16, 2023 11:36
Cannot update Manjaro Linux: Unknown trust with Archlinux-keyring
pacman -Syy
pacman -S archlinux-keyring manjaro-keyring
pacman-key --init
pacman-key --populate archlinux manjaro
pacman-key --refresh-keys
pacman -Syu
foliveira /
Created July 26, 2017 18:38
ykpersonalize -S 06050a0e08170b0f1c11180d16090c1986858a8e88978b8f9c91988d96898c99271e1f202122232425262b9e28
foliveira /
Last active March 1, 2017 13:39
Cardinality Estimation


Counting unique elements of a finite set usually requires linear time/space; this means the bigger the set of unique elements the more time/space it will take us to keep an exact count of unique elements.

A good example of this is the usage of an HashSet - we add an element to a Set (to ensure uniqueness), it gets hashed and stored:

  • In case it's the first one, it is added and that's it;

  • In case it isn't (in case of an hash collision, duplicate value, etc) various things can happen; most common implementations use [Linear Probing][1]

foliveira / count-watchers.js
Last active April 5, 2018 12:50
Tricks for Angular performance
(function () {
var root = angular.element(document.getElementsByTagName('body'));
var countWatchers_ = function(element, scopes, count) {
var scope;
scope =$scope;
if (scope && !(scope.$id in scopes)) {
scopes[scope.$id] = true;
if (scope.$$watchers) {
foliveira / max.ex
Last active August 29, 2015 14:14
Fun with Elixir
defmodule Fun do
def max([x]), do: x
def max([ head | tail ]), do: Kernel.max(head, max(tail))
foliveira / foliveira-yld-entry.json
Last active August 29, 2015 14:09
My bio for the team page
"path": "fabio+oliveira",
"firstName": "Fábio",
"lastName": "Oliveira",
"role": "Node.js",
"longRole": "Node.js Consultant",
"location": "Lisbon, Portugal",
"organization": "YLD Limited",
"bio": "Fábio is a professional Node.js developer, with a huge appetite for learning. Always curious and eager to learn more, he considers himself a full-stack developer and has worked on projects ranging from augmented reality frameworks to realtime analytics products. In his list of interests one can find diverse subjects such has photography, Star Wars, cats and reading 'out-of-the-ordinary' literature.",
"twitter": "fanoliveira",

Keybase proof

I hereby claim:

  • I am foliveira on github.
  • I am foliveira ( on keybase.
  • I have a public key whose fingerprint is F11E 0B4B D7C8 643E 0611 0AC5 D1C6 57CB 6E5B 48DD

To claim this, I am signing this object:

foliveira / process.js
Created January 3, 2014 16:12
Price calculation based on a Index-Tree in Javascript (of Phone Numbers)
function Process(num, h) {
var first_num = num.charAt(0)
var following_nums = num.slice(1)
var first_num_hash_hit = h[first_num]
var following_nums_lookahead = following_nums.charAt(0)
return null
if(following_nums.length === 0)
foliveira / LazyQsort.cs
Created June 28, 2011 16:22 — forked from duarten/LazyQsort.clj
A lazy quick sort
public static IEnumerable<T> LazyQsort<T>(IEnumerable<T> seq, Func<T, T, bool> comp)
if (seq.Any() == false)
return Enumerable.Empty<T>();
var pivot = seq.First();
var xs = seq.Skip(1);
return LazyQsort(xs.Where(x => comp (x, pivot)), comp)