Algorithms Study Helper

TLDR: Automatic scheduler for studying algorithms!

Why?

I wrote this app to help me study for Leetcode-style interview questions. While some believe "memorizing" interview questions is not productive, I find that to be untrue. This is because with interview questions, it's never really "rote" memorization. It requires active thinking to recall the key insights of a solution. With more questions mastered in one's toolbox, new problems definitely become easier to solve. e.g. If you can readily implement MergeSort, divide and conquer type problems would require less mental overhead to crack.

However, while I was trying to study these questions, I noticed I was often either (1) wasting time redoing problems I've already mastered or (2) wasting time having to remaster an old problem that I'd forgotten the key insight to. This app solves that problem by acting as an automatic scheduler.

"Why did you make this app when more mature solutions like Anki exist?"
I did use Anki at first, but I had a difficult time coming up with settings that were suitable for studying interview type questions.

What?

Enter algorithms you want to study into Algorithms Study Helper, and the app will automatically schedule when you should study an algorithm next! As you successfully review an algorithm, it will be scheduled less and less frequently.

How?

This part explains the algorithm I use to schedule when to study problems.

Disclaimer: It is currently tweaked to my own retention/learning rate. Read on to customize it to your liking!

Scheduling Algorithm
nextScheduled = (time when you studied it) + 24 hours * (RETENTION_RATE ^ mastery)

RETENTION_RATE = 2 (default)
This is a constant in prompt.js.
-Increase it if you retain new information well.
-Decrease it if you require more practice to retain information.

Table: Scheduling Intervals with RETENTION_RATE = 2

Mastery	Interval (days)
0	1
1	2
2	4
3	8
4	16
5	32

Each problem you enter into the app is an entry. It is stored in entries.json. An entry looks like this:

const entry = {
	"name": "dijkstra's shortest path algorithm",
	"lastStudied": "Tue Dec 25 2018 22:54:21",
	"nextScheduled": "Wed Dec 26 2018 22:54:21",
	"mastery": 0,
	"subMastery": 3
};

After you review a scheduled problem, you will be asked "How difficult was it?" Your answer affects the entry's subMastery and/or mastery.

1. Easy: subMastery + 4
2. Medium: subMastery + 2
3. Hard: subMastery + 1
4. Buggy Solution: subMastery + 0
5. Failed to Complete: mastery and subMastery both reset to 0.

Once you reach subMastery 4 on an entry, you will gain 1 mastery (up to 5). subMastery is reset to 0.

EXAMPLE: Given a completely new entry with subMastery: 0 and mastery: 0. Say your 4 study sessions look like the following:

1. You answer Medium. (subMastery: 2 and mastery: 0)
   It will be scheduled again in 1 day.
2. You answer Hard. (subMastery: 3 and mastery: 0)
   It will be scheduled again in 1 day.
3. You answer Easy. (subMastery: 0 and mastery: 1)
   It will be scheduled again in 2 days.
4. You answer Easy. (subMastery: 0 and mastery: 2)
   It will be scheduled again in 4 days.

Installation

Navigate into Algorithms-Study-Helper and run:

npm install

Usage

Simply follow the prompts.

node index.js

Modifying entries.json

Modify manually at your own risk! This file contains all your entries. The entries are in order of nextScheduled date. The file is overwritten when the app exits. Only modify entries.json while the app is not running or else it will be overwritten.

Contributing

You're welcome to fork this repo or provide feedback by opening issues!