Nick Yee

Many of you know I'm interested in following Nick Yee's site.
(www.nickyee.com)

On his site he lists the following logic puzzles without answers.

I'm interested to know who gets the answers right first, people in our alliance or people here. I've posted this on both.

Lets see who gets them right :)

And yes I am waiting for new passwords from NCSoft :(

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What follows are two logic puzzles I've found that I think are elegant but which are relatively unknown. To increase the challenge, I will not post the solutions here (nor will I tell you even if you email me). Furthermore, I have altered the phrasings and context such that similar versions of the puzzles can't be easily googled.

1. Amulet Transfer

Galendor and Kellen are two spies working for the same underground organization. Galendor has recently stolen a rare artifact - The Mithril Amulet - from the Queen of Rengefall. Galendor must pass the artifact to Kellen to be transported out of Rengefall but the Queen's henchmen are closing in on them.

Galendor and Kellen are staying in two different rooms in a tavern at the border of Rengefall. Because of the henchmen, neither of them can leave the room tonight for fear of being caught. Thus, the only way that Galendor and Kellen can transfer objects between each other is via the tavern servants.

The problem is that all the servants in the tavern are known to be thieves and will steal anything that is not secure. Both Galendor and Kellen have an iron safe with a large clasp that can be secured with a padlock. Both of them have a padlock and its corresponding key. In other words, there is 1 Amulet, 2 Safes, 2 Padlocks, and 2 correponding Keys.

Anything that is not padlocked in a safe will be stolen by the servants. This includes any unlocked padlocks, keys, and of course the Amulet itself. Given these constraints, how did Galendor manage to transfer the Amulet to Kellen?

2. One Hundred Copper Coins

In Rengefall, copper coins are minted with the portrait of the Queen on one side and the portrait of the King on the other side.

On this day, the half-crazed executioner gives the captured Talin one chance to avoid execution. The executioner brings Talin into an unlit room. He tells Talin that scattered on the table in front of him are one hundred copper coins of which twenty have the Queen side facing up while the rest have the King side facing up. If Talin can separate the coins into two piles, each with the same number of Queens facing up, he will release Talin. One other constraint is that Talin must accomplish this task in 5 minutes. If Talin fails, he will be beheaded.

It is impossible for Talin to see which side the coins are facing up in the darkness, and the contours of the portraits are too similar to decipher by touch. Nevertheless, Talin managed to separate the coins into two piles with the same number of Queens facing up in the time allotted. How did he accomplish this?

(The correct answer does not involve standing coins on their edges. Elegant logic puzzles do not involve semantic loopholes.)

Seeing I still cant access my accounts how about I make this a challenge to NCSoft staff.

Can you get the answer to one or both of these before anyone else at these forums or before ppl in my ally?

Okay, I'm going to take a stab at #2 first.

The guy makes two piles of coins--one with 80 coins and one with 20 coins.

He flips every single coin in the pile of 20 coins...Seems like that should make the number of queens equal in both piles.

It looks good on paper...but my first instinct on these things usually sucks so we'll see!

Okay, I'm going to take a stab at #2 first.

The guy makes two piles of coins--one with 80 coins and one with 20 coins.

He flips every single coin in the pile of 20 coins...Seems like that should make the number of queens equal in both piles.

It looks good on paper...but my first instinct on these things usually sucks so we'll see!

The flaw I see with that. Is how can he tell what is in the 20 pile and what in he 80 pile if he cant see them in the first place

He doesn't HAVE to see what is in each pile...he just has to be able to count and flip.

Neato


You are correct sir.
Very cool

Edit: Wait... no
NM

Edit #2: WAIT
IT IS RIGHT
HAH

Yeh nicely done.

I don't know what Nick's answer is yet but I can't see any problem with yours.

I'll post it after we get an answer to the first one.

I'll take a stab at number 1.

They switched rooms?

Nice lateral thinking but I think this means they cant.

"Because of the henchmen, neither of them can leave the room tonight for fear of being caught."

Well obviously, there has to be a way to do it. But logically thinking, if each of them cannot leave the room, and they cannot trust any of the staff to transfer the amulet, then there would be no way to make the transfer.

Unless a third party was present that was not part of the staff of the inn, that was trusted by both of the spies, then there would be no way for it to happen.

If Talin can separate the coins into two piles, each with the same number of Queens facing up, he will release Talin. One other constraint is that Talin must accomplish this task in 5 minutes.

But are they saying that there needs to be an equal # of queens in each pile? ie, 10 in each? Otherwise, I don't see an issue either.

And as for #1, the rooms are connected? >.> Or through a window? Way too simple a solution, but... Yeah, post the answers when you got an idea Marcus.

Okay, I'm going to take a stab at #2 first.

The guy makes two piles of coins--one with 80 coins and one with 20 coins.

He flips every single coin in the pile of 20 coins...Seems like that should make the number of queens equal in both piles.

It looks good on paper...but my first instinct on these things usually sucks so we'll see!

nice job farty.

in Talin's pile of 20 will be X queens and 20-X kings; in the pile of 80 will be 20-X queens. flip all the coins in the pile of 20 over: 20-X kings become 20-X queens, which is the same number of queens as in the pile of 80!

In the first problem, could Kellen send his unlocked padlock to Galinor? or would it be stolen in transit? I guess I'm not sure if I interpret the 'rules' correctly...

"Anything that is not padlocked in a safe will be stolen by the servants. This includes any unlocked padlocks, keys, and of course the Amulet itself."

I dont know the answer yet either btw

G leaves padlock and key out in plain sight to be seen by servant---padlock and key stolen from G. Then, one might assume a clever servant would place that padlock on K's safe (hoping K would put something in safe and servant would already have that key).
Servant, believing he had key and padlock for K's room would try to return K's initial padlock and key to G's room to replace those so he wouldn't know of original theft.
If G then left stone out....servant would steal stone and lock it for safekeeping in K's room (since only servant would have that key and padlock).
That might get stone locked in K's room but I can't see how K would get possession of it.
This one is hard! lol

for #1, notice that the servants will not steal safes, whether unlocked or not - therein lies the answer. the prob is how do u get the keys to the right person?

#1 is frustrating...

You can send an unlocked safe (I believe) but w/ nothing in it. What good does that do?

You could send a padlocked safe with nothing in it, but again... why?

You could put your key in your safe and padlock it, but then the other guy wouldn't be able to unlock it to get your key out (nor would you, for that matter.)

So basically you can't get your key or padlock to the other guy in a manner that would allow him to use either after he got them.

This reminds me of those riddles where you have certain animals on one side of a river and one raft to get them across and you can't leave this animal or that animal alone together or they'll kill each other, so you have to keep moving them across and back. So I was trying to reason it out like that but I can't figure out how to transport anything to the other person aside from the safe itself!

Think I've got it, but I'm assuming the clasp can be padlocked more than once.
"Both Galendor and Kellen have an iron safe with a large clasp that can be secured with a padlock."


G puts the amulet in the safe and padlocks it and keeps his key.
G sends the safe to K who puts his padlock on also and sends it back to G.
G removes his padlock and sends it back to K.
K unlocks his padlock and has the amulet.

Think I've got it, but I'm assuming the clasp can be padlocked more than once.
"Both Galendor and Kellen have an iron safe with a large clasp that can be secured with a padlock."





G puts the amulet in the safe and padlocks it and keeps his key.
G sends the safe to K who puts his padlock on also and sends it back to G.
G removes his padlock and sends it back to K.
K unlocks his padlock and has the amulet.

ty

Neato


You are correct sir.

OMG...I'm not a SIR!

/emocries