**Update 2018.11.01**: [user:Rezwan.Arefin01,2018-11-01] made a very cool webapp which contains identical problemset, but with more usability. Thank you very much! [You can check it here.](http://codeforces.me/blog/entry/62898#comment-468763)↵
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**Note: There was some updates in 2018.10.05.** See [here](https://codeforces.me/blog/entry/59422?#comment-462081) for changes!↵
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Hello! APIO 2018 is near the end, and IOI 2018 is in this September. I hope you are preparing it well! ↵
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I'm here to present my OI problem checklist : ↵
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![scale=0.6](https://i.imgur.com/K25OVF6r.png)↵
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I used this to train myself in IOI 2015~2016, and to train Korean IOI 2017 Team (probably 2018 too). For long it was in the "beta" phase, but I think it's now good enough to share!↵
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This problemset contains about 300 ~ 400 hard and interesting problems, with appropriate judge links given. (If there is problem in judging, maybe [user:ojuz,2018-05-12] can help that..)↵
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[Google Docs Link](https://docs.google.com/spreadsheets/d/1-kY6uiLOo1AKSBCSjbpGRBZbIldO_3dg6oTRKIJzT-g/edit?usp=sharing)↵
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I hope this can help anyone preparing for future OIs, and a complete answer to the question "How to excel at IOI-style contests" :D
↵
↵
**Note: There was some updates in 2018.10.05.** See [here](https://codeforces.me/blog/entry/59422?#comment-462081) for changes!↵
↵
↵
↵
↵
I'm here to present my OI problem checklist : ↵
↵
![scale=0.6](https://i.imgur.com/K25OVF6r.png)↵
↵
I used this to train myself in IOI 2015~2016, and to train Korean IOI 2017 Team (probably 2018 too). For long it was in the "beta" phase, but I think it's now good enough to share!↵
↵
This problemset contains about 300 ~ 400 hard and interesting problems, with appropriate judge links given. (If there is problem in judging, maybe [user:ojuz,2018-05-12] can help that..)↵
↵
[Google Docs Link](https://docs.google.com/spreadsheets/d/1-kY6uiLOo1AKSBCSjbpGRBZbIldO_3dg6oTRKIJzT-g/edit?usp=sharing)↵
↵
I hope this can help anyone preparing for future OIs, and a complete answer to the question "How to excel at IOI-style contests" :D