22.11.2022, 21:16
I guess there is no consensus about it, but I believe it is acceptable if it is the author himself who provides the solution. After all, many puzzles that are published these days come with a link to a tool that has a "solve" function anyway. Even if not, those who really want to get their hands on the solution without actually solving the puzzle will usually find a way. The Portal is not competitive, so I do not think this should be an issue.
Of course, if the solution is available, it is impossible to determine whether those listed as "solvers" have really finished the puzzle or just copied the answer key. Among other things, anyone who does the latter can also submit a rating (raising doubts regarding the "legitimacy" of such ratings). Again, it is something I do not see as a problem, but others may disagree; this issue has caused heated discussions lately.
Of course, if the solution is available, it is impossible to determine whether those listed as "solvers" have really finished the puzzle or just copied the answer key. Among other things, anyone who does the latter can also submit a rating (raising doubts regarding the "legitimacy" of such ratings). Again, it is something I do not see as a problem, but others may disagree; this issue has caused heated discussions lately.