| Problem | Solutions | Attempts | First Solved |
|---|---|---|---|
| A. Common Problem | 11 | 28 | 0:00:45 |
| B. Making Sets | 0 | 1 | Unsolved |
| C. Cross the houses | 11 | 15 | 0:07:05 |
| D. Hai-Feng Guo's Lift | 5 | 14 | 1:11:01 |
| Problem | Solutions | Attempts | First Solved |
|---|---|---|---|
| A. Common Problem | 11 | 28 | 0:00:45 |
| B. Making Sets | 0 | 1 | Unsolved |
| C. Cross the houses | 11 | 15 | 0:07:05 |
| D. Hai-Feng Guo's Lift | 5 | 14 | 1:11:01 |
