Freely available programming booksIndex
Competitive Programming
- 4Clojure
- A2 Online Judge
- AtCoder
- Binary Search
- Caribbean Online Judge
- COCI
- Codeabbey
- Codechef
- Codecombat
- Codeeval
- CodeFights
- Codeforces
- Codeground
- Coderbyte
- Codewars
- Codingame
- DMOJ
- E-olymp
- Facebook Hackercup
- Google Code Jam
- Google Kickstart
- HackerEarth
- Hackerrank
- Internet Problem Solving Contest
- Just another Golf Coding
- Kattis
- LeetCode
- Microcorruption
- oj.uz
- Sphere Online Judge
- Techgig
- Topcoder
- Toph
- URI Online Judge
Capture the flag
- CTFlearn (email adress requested)
- Google Ctf (email adress requested)
- Hacker101 (email adress requested)
- Hackthebox (email adress requested)
- Overthewire Wargames fungame to practice CTF
- Picoctf (email adress requested)
- TryHackMe (email adress requested)
Data science
Information security
Problem Sets
- 500 Data structures and algorithms interview questions and their solutions in C++
- A2 Online Judge
- Advent Of Code
- Anarchy Golf
- CareerCup
- CheckIO
- Codeforces
- Codility
- Coding Bat
- CSES Problem Set
- Exercism
- Geeks For Geeks
- Google Code Jam - Practise
- Hacker.org
- HackerEarth
- HDU Online Judge
- Interactive Coding Challenge
- InterviewBit
- Kattis
- Leetcode
- Mathproblem of the Month - Bilkent University
- PEG Judge
- PKU Online Judge
- Ponder This!
- Practice Python
- ProblemBook.NET
- Project Euler
- Python Practice Projects
- Rosalind
- Sphere Online Judge
- TalentBuddy
- Timus Online Judge
- URI Online Judge
- UVa Online Judge