| 번호 | 제목 |
|---|---|
| 19001 | Rikka with XOR |
| 19002 | Rikka with Tree Game |
| 19003 | Rikka with Equation |
| 19004 | Rikka with Lines |
| 19005 | Rikka with Bridges |
| 19006 | Rikka with Mutex |
| 19007 | Rikka with Mirror |
| 19008 | Rikka with String |
| 19009 | Equal Digits |
| 19010 | Remove the Tree |
| 19011 | Unseen Segments |
| 19012 | Road Connectivity |
| 19013 | Binary String |
| 19014 | Fair Competition |
| 19015 | Token and Dice |
| 19016 | Convex Region |
| 19017 | Automorphism |
| 19018 | Border |
| 19019 | Convolution |
| 19020 | Decomposition |
