problem-sets

My answers to the problem sets for Aizu, AdventofCode, CodeChef, Codeforces, Codegolf, CSES, Deep-ML, DMOJ, EOlymp, HackerRank, Kattis, KiloNova, Leetcode, LibreOJ, Perl Weekly Review, Project Euler, SPOJ and Timus judges — and more. These solutions are not the most practical or efficient; I have written each submission and their runtime & memory usage within the respective content judge. This is a learning experience of mine, see below what judges are present in the repostiory. also please see issues for making a scraper! :)

Coverage at a glance

• This repository covers problem sets from 25 websites/judges.
• Total problems: 65720 + more...TBD
• Solved: 227
• Progress: ((228 − 1) / 65720) × 100 ≈ 0.3454047474

_{see also: ./prog.sh for summary}

TODO:

Problem Name	Directory
boryas diagnosis	cf/main/879/a
the next palindrome	cc/5
like the bitset	cf/main/2136/b

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Community notes

Discord Server (WIP) I will be coordinating weekly contests, share editorials, compare runtimes/memory, and track personal progress, this will be for enjoying together, furthermore I want to make a /videos/ repository where I upload videos on youtube + more.. about problems and solving them.

• channels (TBD)
  • #announcements — contest schedule, links, and judge picks for the week.
  • #check-in — who is participating this week; start/finish pings.
  • #help — hints only (no full spoilers during live windows).
  • #systems — tooling, IDE setups, scripts (e.g., prog.sh) and benchmarks.
• Weekly cadence:
  • Post schedule every Sunday; run at least one multi-judge set midweek and one weekend set. (when my uni gets bit less workload)
  • Rotate judges so coverage stays broad if thats what people want (Codeforces/CSES/LeetCode/Timus/Project Euler/etc.).
• Participation workflow (TBD):
  1. Check #announcements for the week’s picks.
  2. During the window, work locally; note runtimes/memory on judge submissions.
  3. After lock, share solutions + short commentary in #solutions; add editorials in #editorials.
  4. Log issues/blocks in #help; capture tooling notes in #systems.
• Bot I am very inclined and open to recieving recommendations as to how to make a bot to be able to read submissions and have them, we also have a channel for advent of code golfing using the aoc golf bot

AIM

As of 14/10/2025:

Platform	Solutions
Codeforces	11,353-1
CSES	362
Project Euler	954
LeetCode	3,716+1
Timus	1,199
Deep-ML	187
Perl Weekly Review	343
SPOJ	42573
CodeChef	5033
Kattis	TBD

Solution Status

pie showData
    "Solved" : 223
    "Unsolved" : 65497

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Solution Languages used

pie showData
    "C++" : 97
    "Shell" : 5
    "Python" : 11
    "Haskell" : 4
    "Kotlin" : 1
    "Perl" : 1

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Git Formatting

• When adding a solution file, use platform aliases in commit messages:

  • cf for Codeforces
  • cses for CSES
  • pe for Project Euler
  • lc for LeetCode
  • timus for Timus
  • dml for Deep-ML
  • pwr for Perl Weekly Review
  • spoj for Sphere Online Judge
  • cc for codechef
  • kat for kattis
  • az for aizu
  • hr for hackerrank
  • hdu for hdu
  • kn for kilonova
  • loj for libreoj

• Commit Message Example:

  • Adding a new Codeforces solution:
    cf: solution for problem 123A

• If you add a new file unrelated to problem solutions (e.g., scripts, configs), use the chore or init prefix:

  • chore: add prog.sh for summary automation
  • init: setup initial project structure

Websites mentioned

My answers to the problem sets for these websites/judges (with my original language, just better formatted):

• Advent of Code
• Aizu
• CodeChef
• Codeforces
• CodeGolf
• CSES
• Deep-ML
• DM::OJ
• Eolymp
• HackerRank
• Jane Street
• Kattis
• Kilonova
• LeetCode
• LibreOJ
• LightOJ
• oj.uz
• Perl The Weekly Challenge
• Project Euler
• QOJ.ac
• SphereOJ
• Timus
• TLX
• Toph
• yosupo

Milestones:

0.1 % - 18/08 ?
0.5 %
1 %
5 %
10 %
15 %
20 %
...
100 %

Websites (aliases quick view):

az : onlinejudge.u-aizu.ac.jp
cf : codeforces.com
hdu : acm.hdu.edu.cn
kilonova : kilonova.ro
libreoj : loj.ac

Redundancies:

Problem Name	Presence In	Directory
aplusb	Codeforces (ACMSGURU), Timus, Kilonova, LibreOJ	Timus

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