Diagram

[eupelia]

Is there a mathematical or routine way to figure out when a block precludes a variable from being in a certain spot?

For example on this one, I got the answer wrong because I guessed when I ran out of time. After wards, I wrote out the possibilities and that was the only way that i figured out why the answer was 3:00. But I'm wondering, there must be some sort of formula to this...like if A=size of the largest chunk and B= set of possible positions for the chunk and C= set of possible positions for the variable you are being asked about.

Obviously, I'm over complicating it, but I wonder if there isn't something to it which could actually save me time over trial and error of each possibility. Like in this example U must have at least one item after it and a maximum of 5 items after it so it can fill positions 1 through 5 based on it's own restrictions.
There is chunk that is 2 long which must be placed between 2 and 5, so is there something like 5-2 means position 3 is the only position that cannot be filled by another variable. Ha. i wish it would be that easy.

UGH I should have guessed it was going to probably be something near the middle due to the chunk and then have tried 2, 3 and 4 to start with, but that's still time intensive. I'm probably wasting my time thinking of it. Well, at least I won't forget this problem.

[noah]

Hi Eupelia,

Good question. I agree with your final thought: from the given constraints we should gravitate towards sensing that U will cause a problem in the middle. I don't know of a formula for figuring out middle blocks, and I think there are so many twists and turns that such a formula might end up in the "strict executor" category of strategies, which usually spells trouble.

My diagram for this game -- which did not include the U inference until I faced that question, at which point I added it -- looked like this:


___ ___ ___ ___ ___ ___ S - (YW) - T
1 2 3 4 5 6 U - R
W T T S S S
T W
R U
[all those letters were crossed out, to indicate that they're not possibilities for that slot]

I think the kind of thinking you want to have for that question would be like this (and it sounds like you were pretty much there in your review of it):

"Well, there's a YW chunk that has to go somewhere...where would U mess that up...let me look at 4, the YW chunk couldn't go after, it would have to go before, say 2-3, and T and R could go 5 -6. What about 3? YW couldn't go in 1-2 because S would fall off, so it'd have to be 4-5, but where will U and T go?"

Play the game in about a week to "seal in the freshness"

Tell me if that advice is helpful or just plain annoying! - Noah

[brandblum]

I am at a loss of how to diagram this question. I know the following:

s-yw or wy-t
u-r

Is this correct? How do I connect u-r?

Thanks!

[bbirdwell]

Yep, that's a great way to diagram the constraints.

s -- wy/yw -- t
u -- r

That's what you know. This is not a case where the constraints all add together to form one unified diagram. You've got to make inferences based on these two constraints and attack the game from there, so set up a number line and make some inferences as to which elements CANNOT go in which spaces, and head to the questions! (i.e., R not first, U not last, etc.)

Cheers,
^brian

[lowebrandon477]

Can you draw a picture for this one?

[timmydoeslsat]

[ManhattanPrepLSAT1]

Nice work Timmy! For anyone who's unsure about the box with what looks like a handle across the top, it's a device for notating that the WY chunk can be ordered in either direction.

Personally, I draw a double-headed arrow across the top, and others have come up with other notational devices. The key is, that it certainly is easier than writing out two versions of the tree with WY in both orders.

[matthew.mainen]

I found that frames were useful. Maybe not as useful as they are for some other games, but it definitely obviated the need to think on a few questions.





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