Puzzle 88e364bc: One test solution is logically inconsistent

[Fohlen]

Hi, while trying out puzzle 88e364bc I noticed that the end position for the first test example is (4, 12) as outlined in the first image. However, in the training examples this behaviour is not introduced. Instead, the simpler rule is to terminate any iterative process on collision with its initial direction, which is bottom right. The correct termination block is (8, 16) as shown in the second picture. This follows the ARC principle that a solution should constitute a minimal set of rules. If we already terminate at (4, 12) we need to introduce the additional rule that a transition to the bottom right ALSO collides on the right side.

Please let me know what you think and whether this should be corrected.

[ccocks]

This is confusing. Ideally, I would change it to a problem where this doesn't occur, but since that is likely not possible, I think the "minimal set of rules" should take precedence.

Could you clarify which one was selected "correct"

[Fohlen]

This is confusing. Ideally, I would change it to a problem where this doesn't occur, but since that is likely not possible, I think the "minimal set of rules" should take precedence.

Could you clarify which one was selected "correct"

So far the ARC team has not responded to this case, so I cannot clarify. In my opinion, the second case should be correct.

[SmartManoj]

https://arcprize.org/play?task=88e364bc

What's your inference for the first yellow dot?

Rule: Dot stops when it touches the frame.

[Fohlen]

https://arcprize.org/play?task=88e364bc

What's your inference for the first yellow dot?

Rule: Dot stops when it touches the frame.

Your rule isn’t actually a simple rule, it’s a composite. Move dot into direction unless it touches the frame AND is not in the starting position (where it also touches the frame).

My rule is simpler: move dot unless the indicated direction is blocked. No second condition needed

[SmartManoj]

is not in the starting position (where it also touches the frame).

if it is in the starting position, then it is not moved.

[Fohlen]

is not in the starting position (where it also touches the frame).

if it is in the starting position, then it is not moved.

Yes. As noted before, you have two conditions, I have one (move into direction indicated unless blocked). They are both valid approaches but behave slightly differently in the test case. I argue mine is the simpler condition, therefore the puzzle should be corrected..?

[SmartManoj]

Rule: Dot stops when it touches the frame.

Updated rule: Move dot until it touches the frame again. - single condition.

However, a task is allowed to have at most two solutions.

[Fohlen]

Certainly that’s one way to do it but now you need to count the number of times a dot touches the frame, which is significantly more difficult than simply moving it… I think my argument still stands

[SmartManoj]

Yes, your 2nd solution is correct.

touch rule is not applied here.