International Olympiad in Informatics Training: Path to Gold
This is a 100+ part playbook that takes you from basic C++ programming to a Gold medal at IOI. It has tutorials on 30+ algorithms and data structures, and 75+ problems based on those topics, sorted by increasing difficulty.
IARCS Online Judge is down (giving FATAL for C++ submissions)
Since the last few days, the IARCS website has been down and giving fatal error for C++ submissions. For the time being, I request people to skip the IARCS problems. I've contacted the maintainers, and they said they'll fix it soon. You can still continue making submissions for non-C++ languages.
If you know alternate websites with similar problems, you can help by posting a link to the problem as a reply to the discussion. Tag it with alternate websites, so that it is easy to find.
You can follow this discussion by clicking the thumbs up button. I'll post a reply when they fix it and you'll get a notification.