Problem sources
| Waterloo/Alberta Programming Contest 2004-06-12 | 5 | 4.7Medium |
| Waterloo/Alberta Programming Contest 2005-06-11 | 5 | 5.3Medium |
| Will Code for Drinks 2019/2 | 6 | 5Medium |
| Will Code for Drinks 2021 | 8 | 3.6Medium |
| Will Code for Drinks 2022 | 9 | 4.1Medium |
| Will Code for Drinks 2023 | 10 | 4.4Medium |
| Will Code for Drinks 2024 | 10 | 5.6Hard |