NWERC 2015 remake because Josh never bothered to review it back then
Problem C
Cleaning Pipes — Problem Statistics
Back to problem description| Submissions | 1371 |
| Accepted submissions | 341 |
| Submission ratio | 24.87% |
| Authors | 298 |
| Full solves [?] | 233 |
| Full solve Ratio | 78.19% |