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'queue implemented with a list (dyanmic array) with O(n) time operations'
class Queue:
    def __init__(self):
        self.data = [] # using a python list here instead of array (we need dynamic sizing)

    def enqueue(self, item):
        self.data.append(item)

    def dequeue(self):
        remaining = self.data[1:] # slices from index 1 to the end of the list

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# naive will not work for larger values of N
defmodule FibNaive do
  def n(0), do: 0
  def n(1), do: 1
  def n(2), do: 1
  def n(n), do: n(n - 1) + n(n - 2)
end

# tail-call optimized (employing dynamic programming)
defmodule FibTailCall do

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version: "3.7"

services:
  db:
    environment:
      - POSTGRES_USER=postgres
    image: postgres
    ports:
      - "5432:5432"
    restart: always

wulymammoth

FWIW: I didn't produce the content presented here (the outline from Edmond Lau's book). I've just copy-pasted it from somewhere over the Internet, but I cannot remember what exactly the original source is. I was also not able to find the author's name, so I cannot give him/her the proper credits.

---

Effective Engineer - Notes

• By Edmond Lau
• Highly Recommended 👍
• http://www.theeffectiveengineer.com/

What's an Effective Engineer?

wulymammoth

/*
 * nth-fib in both recursive and iterative (dynamic programming)
 *
 * 0, 1, 1, 2, 3, 5, 8, 13, 21
 */

// time: O(2^N) -- derived from branches (2) to the power of it's maximum depth (N); it is EXPONENTIAL
// space: O(N) -- derived from space used on the call-stack, the recursion will go down to N
function fibRecursive(n) {
  if (n <= 1) return n;

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1. Change your database RDS instance security group to allow your machine to access it.
   • Add your ip to the security group to acces the instance via Postgres.
2. Make a copy of the database using pg_dump
   • $ pg_dump -h <public dns> -U <my username> -f <name of dump file .sql> <name of my database>
   • you will be asked for postgressql password.
   • a dump file(.sql) will be created
3. Restore that dump file to your local database.
   • but you might need to drop the database and create it first
   • $ psql -U <postgresql username> -d <database name> -f <dump file that you want to restore>

• the database is restored

wulymammoth

/*
********************************************************************************
Golang - Asterisk and Ampersand Cheatsheet
********************************************************************************

Also available at: https://play.golang.org/p/lNpnS9j1ma

Allowed:
--------
p := Person{"Steve", 28} 	stores the value

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function add(a, b) {
  return a + b;
}

const cases = [
  // [a, b], expectedAnswer
  [[1, 2], 3], // 3
  [[5,  5], 10],// 10
  [[-1, 2], 1], // 1
  [[1, 1], 2]

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Chapter 1 - Object Oriented Design

The purpose of design is to allow you to do design later, and it's primary goal is to reduce the cost of change.

SOLID Design:

• Single Responsibility Principle: a class should have only a single responsibility
• Open-Closed Principle: Software entities should be open for extension, but closed for modification (inherit instead of modifying existing classes).
• Liskov Substitution: Objects in a program should be replaceable with instances of their subtypes without altering the correctness of that program.
• Interface Segregation: Many client-specific interfaces are better than one general-purpose interface.

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#!/usr/bin/env python
"""
Very simple HTTP server in python.

Usage::
    ./simple_server.py [<port>]

Send a GET request::
    curl http://localhost