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- Competitive Programmer’s Handbook by Antti Laaksonen
- C++ Notes for Professionals book
- Algorithms Notes for Professionals book
- The Ultimate Topic List (with Resources, Problems and Templates) By YouKn0wWho
- C++ tips and tricks By Golovanov399
- I compiled a list of almost all useful blogs ever published on Codeforces By parveen1981
- give this a try (especially if you're feeling down) By rishi
- Useful functions that nobody uses By Qualified
- Useful C++ Tricks By Hikikomorichka