Edabit was my preferred platform until they switched to a subscription model.
- Master DSA fundamentals – Build a solid grasp of core topics like arrays, trees, graphs, recursion, and dynamic programming.
- CodingBat – Rock Solid fundamentals to the Core.
- CodeHS – Basic Practice Problems.
- Edabit – Fun and quick beginner-level problems.
- Codewars (8 kyu problems) – Start with the easiest challenges (8 kyu) to build confidence.
- CodeStepByStep – Guided problems to build logic step-by-step.
- Learn to Program Course on Jutge – Great introductory programming course.
- CodeAbbey – Classic beginner programming challenges.
- GeeksforGeeks – Interview Prep – Start with basic DSA and beginner programming problems.
- 💡
(Before Proceeding.. be aware that for someone to just improve and become good in coding Beginner I is enough, explore those platforms thoroughly)
Move to slightly more challenging platforms to reinforce fundamentals and prepare for intermediate levels.
- Beecrowd – Solve beginner-level algorithm problems.
- Codebreaker – A mix of school-level and beginner competitive problems.
- Reply Challenges – Tech and coding competitions hosted by Reply, including learning resources and foundational programming lessons.
- Introduction to Programming I – ITP1 (Aizu Online Judge) – A well-structured and respected programming series.
- Toph – Focus on easy problems to get used to new formats.
- LeetCode (Easy Problems) – Practice data structures and algorithms with a structured problem set.
- Kattis (Easy Problems) – Filter by difficulty to start with beginner-level tasks.
- Eolymp Basecamp – Follow the Basecamp path for beginner guidance.
- AtCoder Beginner Contests – Compete in or solve past beginner-level contests.
- AtCoder Beginner Contests – Start thinking critically
- AtCoder Rated Contests – Get the taste of real-time contests
- HackerEarth – Structured Learning and Practice II
-
CSES Problem Set
https://cses.fi/problemset -
Kattis – Programming problem sets
https://open.kattis.com -
SPOJ – Wide range of problem sets
https://www.spoj.com/ -
jutge – Ideal for contest practice; used by universities and organizations for programming competitions
https://jutge.org (Best for assignments, exams, contests and to sharpen coding skills for top level coding contests) here is an example problem from The HP CodeWars 2024 Barcelona, Spain. -
Online Judge – ICPC style Problemsets
https://onlinejudge.org
- CodeChef – Get Ready
- Codeforces – Start from low-rated problems (800) — Level Up I
- TopCoder – For advanced contests — Level Up II
- Boot Camp for Beginners (AtCoder)
- Work@Tech - Beginner Problem Set
- GeeksforGeeks - Basic Programming Problems
- GeeksforGeeks - Interview Prep
- AtCoder Beginner Contest Table
- VJudge
- Hangzhou Dianzi University Online Judge
- UVa Online Judge (via VJudge)
- Timus Online Judge
- AIZU Online Judge
- CS Academy
- OJ.uz
- Codebreaker
- Toph
- E-Olymp
- Luogu
- LightOJ
- ACMP
- UOJ
- Yosupo Judge
- PEG Judge
- POJ (Peking University)
- OpenJudge
- VNOI Online Judge
- HDuOJ
- CodeSignal — Practice language specific coding problems for job assessments.
- CodeVS
- 2333 OJ
- Google Code Jam Archive
- Google Tech Dev Guide (Only Guide)
- Reply Challenges
- Work@Tech Practice
- VJudge (UVa Access Article)
- Online Judge Wiki (Code.Fandom)
- AlgoMonster Practice
- BZOJ
- DarkBZOJ
- Szkopuł Problemset
- COCI - Croatian Open Competition in Informatics
- Best Coder @ HDU
- LibreOJ
- A2oJ
- Luogu
- Library Checker
- Vijos
- Jisuanke
- Robocontest (Uzbekistan)
- KEP Contests
- CTFtime
- Cups.online Contests
- NERC Training Info
- NERC Archive
- AlgoTester Events
- Ucup
- BSU ACM Contests
- INF Open - How to Start
- INF Open
- AlgoLeague
- PA-2020-1 @ SIO2
- Potyczki Informatyczne Archive
- AlgoGe
- Yandex Coderun
- CodeSprintLA (UCLA ACM)
- Yandex Intern Training
- Bubble Cup - Problems
- Bubble Cup - Archive
- Sort Me Tasks
- Sort Me
- Yandex Contests
- Supecoder Questions
- Midnight Code Cup
- NERC Training Information
- CP Algorithms
- TeamsCode
- CodeAny Competitions
- Kilonova
- HighLoad.fun
- Codility Challenges
- CerealCodes Summer 2023
- CerealCodes Homepage
- Codeforces Gym 104521 (Novice)
- MIT IT
- Calico @ Berkeley
- Calico Judge Problems
- Contest Pizza
- IPSC
- LIT Competition
- Coding Contest Registration
- CodeBattle India
- Solve.by
- CodeAbbey
- Rosalind Bioinformatics Problems
- LintCode Problem List
- Code Golf
- AdventJS
- TJU Online Judge Training
- AlgoTester Homepage
- TJU Online Judge Home
- CoderOJ
- Baekjoon Online Judge (BOJ)
- Solved.ac (Korean BOJ tracker)
- KOI (Korean Olympiad in Informatics)
- Jungol (Korean)
- CodeUp (Korean)
- SoftEeR (Korean)
- Programmers (Korean)
- Dovelete (Korean)
- SW Expert Academy (Samsung)
- NYPC - Nexon Youth Programming Challenge
- CodeGround by Samsung (Korean)
- ICPC Asia West Continent
- ICPC Kanpur
- ICPC Asia Amritapuri Regional Contest
- ICPC Problem set Archives
- ICPC Official Website – Welcome to CP, LezGooooo..!!
Knowing how to use these platforms mindfully is key.
Start filtering from low-rated problems and gradually push your limits.
🔑 Learn to extract maximum value:
- For example, LeetCode offers:
- Curated Blind 75
- Must-Do 150 problem set
- Topic-wise filters for focused practice
“Quality > Quantity”
- Revisit solved problems
- Re-solve using:
- A fresh new approach
- An old approach with added constraints
- A more efficient method
This cultivates deeper understanding and decodes problem-solving patterns.
Don’t solve blindly — solve mindfully. That's where real growth happens.
Walk this path with unwavering focus and passion, and you just might carve your name into the hall of fame of the world’s most elite coders.
(for fast paced approach or for quick interview preparation, there is no harm in following the curated path created created by the (Genuine) Tech content creators on social media platforms like instagram or threads, for example, I follow an account named leetcodedaybyday on threads, he keeps posting solutions of leetcode interview problems with explanations and I have also saved some instagram reels where people have shared their learning path/DSA sheets or problem solving patterns for cracking 40 or 50 lpa jobs by just mastering DSA in no time, some creators have also shared frequently asked problems, algorithms and problem solving patterns along with solutions, this is also an effective approach because I have heard people say : " I have wasted time solving 500-600 problems on leetcode instead of focusing on some important problem solving patterns and some important questions") reference
Happy Coding 🚀
Push your limits, one problem at a time.
Original message.