hughdbrown

System design interview framework

Sam Gavis-Hughson

1. Understand the details of the system
2. Simple high-level architecture
3. Optimize
4.   ....

1. What is your interviewer asking?

hughdbrown

Building and deploying web/react apps
https://mherman.org/
https://testdriven.io/

14 Patterns to Ace Any Coding Interview Question | Hacker Noon
https://hackernoon.com/14-patterns-to-ace-any-coding-interview-question-c5bb3357f6ed

Free Amazon AWS Tutorial - AWS Essentials (2019)
https://www.udemy.com/course/linux-academy-aws-essentials-2019/

hughdbrown

from math import log
from collections import Counter


class TFIDF(object):
    def __init__(self, corpus):
        self.corpus = corpus
        self.ndocs = len(corpus)
        self.documents = [Counter(doc.split()) for doc in corpus]
        self.words = sum(sum(doc.values()) for doc in self.documents)

hughdbrown

Jason McGhee on tabular data with neural networks
https://www.youtube.com/watch?v=WPQOkoXhdBQ&t=

hughdbrown

import asyncio
import json
import websockets
​
async def subscribe_to_exchange():
    async with websockets.connect('wss://ws-feed.gdax.com') as websocket:
        subscribe = {
            "type": "subscribe",
            "product_ids": ["BTC-USD"],
            "channels": ["full"]

hughdbrown

https://www.geeksforgeeks.org/how-to-prepare-for-amazon-software-development-engineering-interview/
http://highscalability.com/amazon-architecture
https://www.aboutamazon.com/working-at-amazon/our-leadership-principles

hughdbrown

# Websockets
https://developer.mozilla.org/en-US/docs/Web/API/WebSockets_API/Writing_WebSocket_client_applications

# Michael Herman
https://mherman.org/
https://testdriven.io/

# Asyncio in python
https://www.integralist.co.uk/posts/python-asyncio/

hughdbrown

https://www.coursera.org/learn/algorithms-part1
https://www.edx.org/course/cs50s-introduction-to-computer-science
https://www.coursera.org/specializations/deep-learning
https://www.udemy.com/course/the-complete-web-development-bootcamp/
https://www.coursera.org/learn/python
https://www.coursera.org/specializations/algorithms
https://www.coursera.org/learn/learning-how-to-learn
https://www.coursera.org/specializations/software-design-architecture

https://machinelearningmastery.com/rfe-feature-selection-in-python/

hughdbrown

bisect: bisect_left and bisect_right
itertools: tee, count, accumulate, chain, groupby; takewhile, dropwhile
collections: defaultdict, Counter, deque; namedtuple, ChainMap useful for applications
heapq: heapify, heappush, heappop
functools: reduce, partial

hughdbrown

from typing import List

class FenwickTree(object):
    def __init__(self, n):
        self.t = [1] * (n + 1)
        self.n = n
        self.d = {i: (i & (-i)) for i in range(n)}
        self.build(self.t)
    #
    def build(self, t: List[int]):