| Problem Name | Online Judge | Contest | Difficulty Level | |
|---|---|---|---|---|
| 1 | Anton and Permutation | Codeforces | Codeforces Round #404 (Div. 2) | 7 |
| 2 | The Untended Antiquity | Codeforces | Codeforces Round #439 (Div. 2) | 7 |
| 3 | Iahub and Xors | Codeforces | Codeforces Round #198 (Div. 1) | 7 |
| 4 | Subtree Minimum Query | Codeforces | Educational Codeforces Round 33 (Rated for Div. 2) | 8 |
| 5 | Andryusha and Nervous Barriers | Codeforces | ?????????? 2017 - ????? (?????? ??? ??????-??????????) | 9 |