Merge branch 'master' of github.com:lamccloskey/leetcode-patterns

Author: lamccloskey

.github/workflows/github-pages.yml

@@ -0,0 +1,41 @@
+name: github-pages
+
+on:
+  push:
+    branches:
+      - master
+
+  workflow_run:
+    workflows: [run-cron]
+    types:
+      - completed
+
+  workflow_dispatch:
+
+jobs:
+  build-and-deploy:
+    runs-on: ubuntu-20.04
+    steps:
+      - name: Checkout Repository
+        uses: actions/checkout@v3
+
+      - name: Install dependencies and build
+        uses: actions/setup-node@v3
+        with:
+          node-version: '14'
+      - run: npm ci
+      - run: npm run build
+
+      - name: Check GitHub Pages status
+        uses: crazy-max/ghaction-github-status@v3
+        with:
+          pages_threshold: major_outage
+
+      - name: Deploy to gh-pages branch
+        if: success()
+        uses: crazy-max/ghaction-github-pages@v3
+        with:
+          target_branch: gh-pages
+          build_dir: build
+        env:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}

.github/workflows/run-cron.yml

@@ -0,0 +1,27 @@
+name: run-cron
+
+on:
+  schedule:
+    - cron: '0 12 * * 0'
+
+  workflow_dispatch:
+
+jobs:
+  update:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v3
+      - uses: actions/setup-python@v4
+        with:
+          python-version: '3.x'
+          architecture: 'x64'
+      - run: |
+          python -m pip install --upgrade pip
+          pip install requests python-leetcode
+      - run: |
+          python cron/update_questions.py
+        env:
+          LEETCODE_SESSION_TOKEN: ${{ secrets.LEETCODE_SESSION_TOKEN }}
+      - uses: stefanzweifel/git-auto-commit-action@v4
+        with:
+          commit_message: Update questions via run-cron GitHub Action

.gitignore

@@ -23,3 +23,5 @@
 npm-debug.log*
 yarn-debug.log*
 yarn-error.log*
+
+__pycache__

README.md

@@ -1,14 +1,12 @@
-# Leetcode Patterns
+# Leetcode Patterns [![github-pages](https://github.com/seanprashad/leetcode-patterns/actions/workflows/github-pages.yml/badge.svg)](https://github.com/seanprashad/leetcode-patterns/actions/workflows/github-pages.yml) [![run-cron](https://github.com/seanprashad/leetcode-patterns/actions/workflows/run-cron.yml/badge.svg)](https://github.com/seanprashad/leetcode-patterns/actions/workflows/run-cron.yml)
 
 ## Table of Contents
 
 - [Background](#background)
-- [Preface](#preface)
+- [Fundamentals](#fundamentals)
 - [Notes](#notes)
 - [Question List](#question-list)
 - [Solutions](#solutions)
-- [Leetcode Discuss](#leetcode-discuss)
-- [Tips to Consider](#tips-to-consider)
 - [Suggestions](#suggestions)
 - [Acknowledgements](#acknowledgements)
 
@@ -22,10 +20,11 @@ repeatedly applying common patterns rather than randomly tackling questions.
 
 All questions are available on [leetcode.com] with some requiring [leetcode premium].
 
-## Preface
+## Fundamentals
 
-It is highly recommended to read chapters 1, 2, 3, 4, 8, and 10 of [Cracking The Coding Interview]
-to familiarize yourself with the following data structures and their operations:
+To find the greatest amount of success when practicing, it is highly recommended
+to know the methods and runtimes of the following data structures and their
+operations:
 
 - Arrays
 - Maps
@@ -45,7 +44,7 @@ In addition, you should have a good grasp on common algorithms such as:
 
 ## Notes
 
-[This pdf] contains useful information for the built-in data structures in Java.
+[This pdf] contains information for the main data structures in Java.
 
 Other useful methods to know include [`substring()`](https://docs.oracle.com/javase/8/docs/api/java/lang/String.html#substring-int-int-), [`toCharArray()`](https://docs.oracle.com/javase/8/docs/api/java/lang/String.html#toCharArray--), [`Math.max()`](https://docs.oracle.com/javase/8/docs/api/java/lang/Math.html#max-int-int-),
 [`Math.min()`](https://docs.oracle.com/javase/8/docs/api/java/lang/Math.html#min-int-int-), and [`Arrays.fill()`](https://docs.oracle.com/javase/8/docs/api/java/util/Arrays.html#fill-int:A-int-).
@@ -55,62 +54,10 @@ Other useful methods to know include [`substring()`](https://docs.oracle.com/jav
 The entire question list can be found here:
 https://seanprashad.com/leetcode-patterns/.
 
-In addition to viewing the question list, companies that have previously asked
-the question in the past 6 months (_as of May 2021_) will be listed. You can
-also use the checkboxes to mark which questions you've completed!
-
 ## Solutions
 
 Solutions written in Java can be found in the [solutions] branch.
 
-## Leetcode Discuss
-
-[Leetcode discuss] is an amazing resource and features previous interview
-questions, as well as compensation and general career advice.
-
-## Tips to Consider
-
-```
-If input array is sorted then
-    - Binary search
-    - Two pointers
-
-If asked for all permutations/subsets then
-    - Backtracking
-
-If given a tree then
-    - DFS
-    - BFS
-
-If given a graph then
-    - DFS
-    - BFS
-
-If given a linked list then
-    - Two pointers
-
-If recursion is banned then
-    - Stack
-
-If must solve in-place then
-    - Swap corresponding values
-    - Store one or more different values in the same pointer
-
-If asked for maximum/minimum subarray/subset/options then
-    - Dynamic programming
-
-If asked for top/least K items then
-    - Heap
-
-If asked for common strings then
-    - Map
-    - Trie
-
-Else
-    - Map/Set for O(1) time & O(n) space
-    - Sort input for O(nlogn) time and O(1) space
-```
-
 ## Suggestions
 
 Think a question should/shouldn't be included? Wish there was another feature?
@@ -119,18 +66,13 @@ Feel free to open an [issue] with your suggestion!
 ## Acknowledgements
 
 This list is heavily inspired from [Grokking the Coding Interview] with
-additional problems extracted from the [Blind 75 list] and this medium article
+additional problems extracted from the [Blind 75 list] and this hackernoon article
 on [14 patterns to ace any coding interview question].
 
 [leetcode.com]: https://leetcode.com
 [leetcode premium]: https://leetcode.com/subscribe/
 [this pdf]: https://drive.google.com/open?id=1ao4ZA28zzBttDkuS6MLQI52gDs_CJZEm
-[cracking the coding interview]: http://www.crackingthecodinginterview.com/contents.html
-[here]: https://hackernoon.com/14-patterns-to-ace-any-coding-interview-question-c5bb3357f6ed
-[topcoder]: https://www.topcoder.com/community/competitive-programming/tutorials/dynamic-programming-from-novice-to-advanced/
-[back to back swe youtube channel]: https://www.youtube.com/watch?v=jgiZlGzXMBw
 [solutions]: https://github.com/SeanPrashad/leetcode-patterns/tree/solutions
-[leetcode discuss]: https://leetcode.com/discuss/interview-question
 [grokking the coding interview]: https://www.educative.io/courses/grokking-the-coding-interview
 [issue]: https://github.com/SeanPrashad/leetcode-patterns/issues/new
 [blind 75 list]: https://www.teamblind.com/article/New-Year-Gift---Curated-List-of-Top-100-LeetCode-Questions-to-Save-Your-Time-OaM1orEU?utm_source=share&utm_medium=ios_app

cron/update_questions.py

@@ -0,0 +1,132 @@
+import os
+import json
+import leetcode
+import leetcode.auth
+from datetime import datetime
+from leetcode.rest import ApiException
+
+
+def create_leetcode_api():
+    LEETCODE_SESSION_TOKEN = os.environ.get("LEETCODE_SESSION_TOKEN")
+    csrf_token = os.environ.get("LEETCODE_CSRF_TOKEN")
+
+    configuration = leetcode.Configuration()
+
+    configuration.api_key["x-csrftoken"] = csrf_token
+    configuration.api_key["csrftoken"] = csrf_token
+    configuration.api_key["LEETCODE_SESSION"] = LEETCODE_SESSION_TOKEN
+    configuration.api_key["Referer"] = "https://leetcode.com"
+    configuration.debug = False
+
+    return leetcode.DefaultApi(leetcode.ApiClient(configuration))
+
+
+def get_question_metadata(api, title_slug):
+    graphql_request = leetcode.GraphqlQuery(
+        query='''query questionData($titleSlug: String!) {
+            question(titleSlug: $titleSlug) {
+                title
+                difficulty
+                companyTagStats
+                isPaidOnly
+            }
+        }
+        ''',
+        variables=leetcode.GraphqlQueryGetQuestionDetailVariables(
+            title_slug=title_slug)
+    )
+
+    try:
+        response = api.graphql_post(body=graphql_request)
+        return response
+    except ApiException as e:
+        print(
+            f'Exception occurred when contacting the Leetcode GraphQL API: ${e}')
+        exit()
+
+
+def construct_company_tag_list(company_tags_json, sections):
+    companies = []
+
+    for section in sections:
+        for company in company_tags_json[section]:
+            companies.append({
+                "name": company["name"],
+                "slug": company["slug"],
+                "frequency": company["timesEncountered"]
+            })
+
+    return sorted(companies, key=lambda d: d['frequency'], reverse=True)
+
+
+def update_question_metadata(question, response):
+    print(f'''🔄 Updating question metadata for {question["title"]}''')
+
+    question_title = response.data.question.title
+    question_difficulty = response.data.question.difficulty
+    question_company_tags = json.loads(
+        response.data.question.company_tag_stats)
+    question_is_premium = response.data.question.is_paid_only
+
+    # Retrieve companies who have asked this question for the following two
+    # company_tag_stat sections:
+    #   1. 0-6 months
+    #   2. 6 months to 1 year
+    companies = construct_company_tag_list(
+        question_company_tags, ["1", "2"])
+
+    question["title"] = question_title
+    question["difficulty"] = question_difficulty
+    question["companies"] = companies
+    question["premium"] = question_is_premium
+
+
+def read_questions(file_name):
+    print(f"💾 Loading {file_name}")
+
+    try:
+        with open(file_name, "r") as file:
+            questions = json.load(file)
+            print(f"✅ Finished loading {file_name}")
+            return questions
+    except Exception as e:
+        print(
+            f"❌ Exception occurred when reading {file_name}: {e}")
+        exit()
+
+
+def write_questions(file_name, questions):
+    print(f"💾 Updating {file_name}")
+
+    try:
+        with open(file_name, "w") as file:
+            questions["updated"] = str(datetime.now().isoformat())
+            json.dump(questions, file, indent=2)
+            print(f"✅ Finished updating {file_name}")
+    except Exception as e:
+        print(
+            f"❌ Exception occurred when writing {file_name}: {e}")
+        exit()
+
+
+def main(file_name):
+    api = create_leetcode_api()
+    questions = read_questions(file_name)
+
+    for question in questions["data"]:
+        title_slug = question["slug"]
+
+        response = get_question_metadata(api, title_slug)
+
+        update_question_metadata(question, response)
+
+    write_questions(file_name, questions)
+
+
+if __name__ == "__main__":
+    file_name = os.getcwd() + "/src/data/questions.json"
+    startTime = datetime.now()
+
+    main(file_name)
+
+    print(f"⏱️  Data updated in {datetime.now() - startTime} seconds")