The Puzzle Thread

[Litodude]

Re: The Puzzle Thread

i was told this back in highschool, though i've changed it a bit.

you are stuck in a room.

this room has a door, and a transparent floating screen.

the room is metallic.

the door is metallic. 

the screen is intangible and unbreakable..

the knob is metallic, and has no significant features other than an engraving which signifies the direction in which the knob is to be turned. 

the hinges which the door turns upon, is on the other side, indicating the door is turned away from you.

you are given a lighter. this lighter is unbreakable, and immovable apart from its intended function: to light.

you are given four pieces of string. the pieces of string non-uniformly burn for 30 minutes each. 

you are given a 5x5 cm piece of cloth. the cloth is neatly folded and can fit in between the cracks of the door

you are given a pencil. it is sharpened and #2.

the floating screen indicates: "the door will only open after precisely 45 minutes of time elapses, no sooner, no more - otherwise you are electrocuted  upon twisting the knob. 

your body can only handle two electrocutions before dying. if you cannot exit within 2 hours you will be killed."

it then counts down: 5, 4, 3, 2, 1, GO.

how do you get out?

edit- grmamarrar

[Evnoir]

Re: The Puzzle Thread

After you hear GO, take one of the strings and light it at both ends. Precisely after the first string completely burns, light the second string at one end only.
In the mean time, you can take the piece of cloth and write down with your pencil a sudoku puzzle you wanted to solve:

+-------+-------+-------+
| 8 7 9 | 4 3 1 | 6 5 2 |
| 6 2 3 | 5 9 7 | 1 4 8 |
| 1 5 4 | 2 6 8 | 7 9 3 |
+-------+-------+-------+
| 4 3 2 | 8 1 6 | 5 7 9 |
| 5 1 7 | 9 4 3 | 8 2 6 |
| 9 6 8 | 7 5 2 | 4 3 1 |
+-------+-------+-------+
| 7 9 6 | 3 8 4 | 2 1 5 |
| 3 4 1 | 6 2 5 | 9 8 7 |
| 2 8 5 | 1 7 9 | 3 6 4 |
+-------+-------+-------+

While you wait for the rest of the string to burn, you suddenly realize that the solution to igot's riddle was that

the poles are beside each other.

When the second string completely burns out, 45 minutes have elapsed and the door will be open.

Reincarnate's riddle is still boggling my mind.

@Zapmeister: I couldn't solve the puzzle and this post was just more for laughs than for solutions. When I solved for all the potential numbers, there was only one spot (6th row, 8th column) that had 2 possible numbers. All the rest were 3+ so I gave up lol

[Litodude]

Re: The Puzzle Thread

gj

[MinaciousGrace]

Re: The Puzzle Thread

y do they call it circular logic

[igotrhythm]

Re: The Puzzle Thread

After you hear GO, take one of the strings and light it at both ends. Precisely after the first string completely burns, light the second string at one end only.
In the mean time, you can take the piece of cloth and write down with your pencil a sudoku puzzle you wanted to solve:

+-------+-------+-------+
| 8 7 9 | 4 3 1 | 6 5 2 |
| 6 2 3 | 5 9 7 | 1 4 8 |
| 1 5 4 | 2 6 8 | 7 9 3 |
+-------+-------+-------+
| 4 3 2 | 8 1 6 | 5 7 9 |
| 5 1 7 | 9 4 3 | 8 2 6 |
| 9 6 8 | 7 5 2 | 4 3 1 |
+-------+-------+-------+
| 7 9 6 | 3 8 4 | 2 1 5 |
| 3 4 1 | 6 2 5 | 9 8 7 |
| 2 8 5 | 1 7 9 | 3 6 4 |
+-------+-------+-------+

While you wait for the rest of the string to burn, you suddenly realize that the solution to igot's riddle was that

the poles are beside each other.

When the second string completely burns out, 45 minutes have elapsed and the door will be open.

Reincarnate's riddle is still boggling my mind.

I love how you strung all 3 solutions together like that.

I have three legs, but cannot stand
I have two eyes, but cannot see
And yet, I can see very far, but nothing can be distinguished
I am constantly starving, yet always full
And if you look for me, I can never be found.

What am I?

The Ironman Triathlon. Three legs (swimming, biking, running); two I's; sees very far (over 100 miles!); always full (of participants)...but the last line is stumping me.

[Zapmeister]

Re: The Puzzle Thread

+-------+-------+-------+
| 8 7 9 | 4 3 1 | 6 5 2 |
| 6 2 3 | 5 9 7 | 1 4 8 |
| 1 5 4 | 2 6 8 | 7 9 3 |
+-------+-------+-------+
| 4 3 2 | 8 1 6 | 5 7 9 |
| 5 1 7 | 9 4 3 | 8 2 6 |
| 9 6 8 | 7 5 2 | 4 3 1 |
+-------+-------+-------+
| 7 9 6 | 3 8 4 | 2 1 5 |
| 3 4 1 | 6 2 5 | 9 8 7 |
| 2 8 5 | 1 7 9 | 3 6 4 |
+-------+-------+-------+

did you actually spot the clever way to do it or did you cheat

because i'm pretty sure this isn't brute-forceable with pencil and paper within a reasonable length of time

:P

[Litodude]

Re: The Puzzle Thread

I have three legs, but cannot stand
I have two eyes, but cannot see
And yet, I can see very far, but nothing can be distinguished
I am constantly starving, yet always full
And if you look for me, I can never be found.

What am I?

a smartphone on a charging phone dock with its camera open

[Arntonach]

Re: The Puzzle Thread

I have three legs, but cannot stand
I have two eyes, but cannot see
And yet, I can see very far, but nothing can be distinguished
I am constantly starving, yet always full
And if you look for me, I can never be found.

What am I?

Sums up my stepdad pretty well lol

Gonna take a stab at this and say yatagarasu?

[FoJaR]

Re: The Puzzle Thread

ravensburger

[LongGone]

Re: The Puzzle Thread

Here's a puzzle from one of my favourite puzzle books:

=========================
A few years ago, I did an experiment on four men in a room. Each men are presented four cabinets containing there drawers each. They are told that in each drawer there is either an apple, or an orange. The men are also told that one cabinet contained three apples, one contained three oranges, one contained two apples and an orange, the final contained an apple and two oranges.

Four labels labelled AAA, OOO, AAO and AOO (for Apple and Orange respectively) are placed on the four different cabinets. The men are told that each cabinet's label are wrong. The men are assigned a cabinet each, and each man cannot see the other men's labels. The men then can open two drawers from his cabinet and try to guess the content of the third drawer.

I couldn't remember exactly the contents of each drawer, as my assistant was the one who prepared them. So I challenged myself to guess the contents based on what the men said.

The first man opens two drawers and says "I see two apples - and I know what's in my third drawer". The second man opens two drawers and says "I see an apple and an orange - and I know what's in my third drawer".

The third man said "I see two oranges - and.." but alas, I can't remember if he said he could tell the contents of his third drawer. He did say yes or no however, and based on that I could figure out with 100% certainty the contents of all four cabinets and what labels were on them.

Can you?
=========================

[leonid]

Re: The Puzzle Thread

My take on cabinet puzzle

The first man's cabinet is labeled either AAA or AAO
The second man's cabinet is labeled either AAO or AOO

Case 1: The third man said yes -> his cabinet is labeled either OOO or AOO
Case 1.1: The first man's cabinet is labeled AAA

cabinet| 1 | 2 | 3 | 4 |
label  |AAA|   |   |   |
content|   |   |   |   |

cabinet| 1 | 2 | 3 | 4 |
label  |AAA|   |   |   |
content|AAO|   |   |   |
Cabinet #1 contains two apples and can't be AAA

cabinet| 1 | 2 | 3 | 4 |
label  |AAA|AAO|   |   |
content|AAO|AOO|   |   |
Cabinet #2 contains one apple and one orange and can't be AAO

cabinet| 1 | 2 | 3 | 4 |
label  |AAA|AAO|AOO|   |
content|AAO|AOO|OOO|   |
Cabinet #3 contains two oranges and can't be AOO

cabinet| 1 | 2 | 3 | 4 |
label  |AAA|AAO|AOO|OOO|
content|AAO|AOO|OOO|AAA|

Case 1.2: The first man's cabinet is labeled AAO

cabinet| 1 | 2 | 3 | 4 |
label  |AAO|   |   |   |
content|   |   |   |   |

cabinet| 1 | 2 | 3 | 4 |
label  |AAO|   |   |   |
content|AAA|   |   |   |
Cabinet #1 contains two apples and can't be AAO

cabinet| 1 | 2 | 3 | 4 |
label  |AAO|AOO|   |   |
content|AAA|AAO|   |   |
Cabinet #2's label can't be AAO
Cabinet #2 contains one apple and one orange

cabinet| 1 | 2 | 3 | 4 |
label  |AAO|AOO|OOO|   |
content|AAA|AAO|AOO|   |
Cabinet #3's label can't be AOO
Cabinet #3 contains two oranges

cabinet| 1 | 2 | 3 | 4 |
label  |AAO|AOO|OOO|AAA|
content|AAA|AAO|AOO|OOO|

We can't tell the cabinet's contents if the third person said "yes" because there are two possible outcomes


Case 2: The third man said no -> his cabinet is labeled either AAA or AAO

cabinet| 1 | 2 | 3 | 4 |
label  |   |AOO|   |   |
content|   |   |   |   |
Label AAA and AAO must be taken by cabinet #1 and #3 in some order,
So cabinet #2's label can only be AOO

cabinet| 1 | 2 | 3 | 4 |
label  |   |AOO|   |   |
content|   |AAO|   |   |
Cabinet #2 contains one apple and one orange and can't be AOO

cabinet| 1 | 2 | 3 | 4 |
label  |   |AOO|   |   |
content|AAA|AAO|   |   |
Cabinet #1 contains two apples and can't be AAO

cabinet| 1 | 2 | 3 | 4 |
label  |AAO|AOO|AAA|   |
content|AAA|AAO|   |   |
Cabinet #1's label can't be AAA

cabinet| 1 | 2 | 3 | 4 |
label  |AAO|AOO|AAA|OOO|
content|AAA|AAO|   |   |

cabinet| 1 | 2 | 3 | 4 |
label  |AAO|AOO|AAA|OOO|
content|AAA|AAO|OOO|   |
Cabinet #4 can't be OOO

cabinet| 1 | 2 | 3 | 4 |
label  |AAO|AOO|AAA|OOO|
content|AAA|AAO|OOO|AOO|

Third person said "no" and we figured out the cabinet's contents with 100% certainty

[LongGone]

Re: The Puzzle Thread

[choof]

Re: The Puzzle Thread

What does the fox say

stepmania

[Reach]

Re: The Puzzle Thread

One of my favorite ultra hard problems (some of you might have seen it before, since I've posted it before. IIRC Reincarnate was the only one to solve it correctly, so don't you dare post the answer :P ):

What is the maximum number of cells that cannot further be further subdivided, formed by the interpenetration of 3 cubes?

[Zapmeister]

Re: The Puzzle Thread

@Zapmeister: I couldn't solve the puzzle and this post was just more for laughs than for solutions. When I solved for all the potential numbers, there was only one spot (6th row, 8th column) that had 2 possible numbers. All the rest were 3+ so I gave up lol

here's the clever solution.

the puzzle is symmetric on the main diagonal.

if you flip the puzzle on that diagonal then all that happens is the 1 swaps with 9, the 6 swaps with 7, the 3 swaps with 5, and the 248 all stay where they are.

so if you flip the puzzle along the diagonal and then relabel the numbers like that, you get the same puzzle.

because i told you explicitly that the puzzle has a unique solution, the solution grid must have the property that if you flip it and relabel the numbers, you get the same solution.

in particular the numbers on the diagonal can't change, so they have to be 2s, 4s or 8s. once you know this the puzzle solves with singles and pairs.

bruteforcing will get you nowhere because SE rates it 11.3 which makes it significantly harder than the puzzle in awein999's thread, and there is no solution to this similar to how i solved that puzzle, because this one doesn't have any exotic patterns up to five numbers.


edit: the answer to my other puzzle was this