The HARDEST Logic Puzzle Ever (Simpler Version): Two Doors To Freedom Riddle

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An evil warden holds you prisoner, but offers you a chance to escape. There are 3 doors A, B, and C. Two of the doors lead to freedom and the third door leads to lifetime imprisonment, but you do not which door is what type. You are allowed to point to a door and ask a single yes-no question to the warden. If you point to a door that leads to freedom, the warden does answer your question truthfully. But if you point to the door that leads to imprisonment, the warden answers your question randomly, either saying "yes" or "no" by chance. Can you think of a question and figure out a way to escape for sure?

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If he is an evil warden, all the doors would lead to imprisonment and the whole ordeal would have been a cruel joke.

jashton
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Hey thanks man ii was stuck in this situation a while back but then I remembered your video and now I'm free

sarahbnyakar
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thought for a sec it'd be the "lions who haven't eaten in 3 years" riddle lol

NXeta
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Oh. That's a simple solution.
I envisioned asking something like a paradoxical question, or something he can't know the answer to like "is the third character of my email password a 'g'?"
If he answers yes or no, then it's the imprisonment door. If it's a freedom door he'll answer "truthfully": "I don't know" or "there is no answer."

AstroTibs
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This reminds me of the riddle concerning two doors (one leading to freedom, the other to certain death / imprisonment, but you don't know which is which) and two guards (one always answers truthfully, the other always lies, but again you don't know which).

In that scenario, the best question is apparently "If I asked the other guard which door leads to freedom, what would he say?", then you take the _other_ door, as the question guarantees you'll get the wrong answer.

mittfh
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I really liked this problem. At first, I thought how can a random answer provide information but then I realized that the answer was not always random. And this small difference allows for a solution. In my mind, I created a table instead of a tree.

Door A Door B Door C Answer
Freedom Freedom Prison Yes
Freedom Prison Freedom No
Prison Freedom Freedom Yes or No

Of course, the result is the same — yes pick door B, no pick door C.

SridevHumphreys
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wtf kinda warden gives you a 2/3 chance for escape, then lets you ask a question?

MCKoolperson
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My first thought was to ask a paradox question (something like "will you say no?") so he'll be stumped if he tries to tell the truth

moonythespoonie
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I came up with, point at door 1 and ask "does the door i'm pointing at have the same outcome as door 2?"
if he says yes, you pick door 2 (because if it was the truth then door 2 will work, and if he says no then door 1 was the imprisonment door, so door 2 has to lead to freedom)
if he says no you pick door 3 (because if it was the truth then either door 1 or 2 are the imprisonment door, and if it was a lie then door 1 or 2 have to lead to imprisonment)

hoppz
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I thought about pointing at one door and asking if his answer will be no.
If it leads to freedom he can not answer truthfully and thus will say nothing,
if he answers, regardless of the answer it must be a random answer and thus the other two doors must lead to freedom.

akiranishiki
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My awnser:
I would point to A and ask if either A or B leads to inprisonment.
If he says Yes, choose C.
If he says No, choose B.
because if he says No either C is inprisonment or he is lying thus A being inprisonment.
Always fun!

sjege
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I'm almost positive that this will actually happen to me at some point, and I won't remember how this works.

Scott.Sandifer
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That took me a bit, but it was clever. I thought, "I don't want to have to choose to go through the random one" and was able to work it out but it was stimulating. Nice

icannotchoose
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Before I see the answer this is my solution:

Point to the middle door and ask “Does the door on the left lead me to freedom”
If the answer is yes go through the left door, otherwise go through the right one

If the door in the middle was freedom then he will tell you if the door is safe, or in the other hand which one is not, leaving u with the right door which would be guaranteed to have freedom

You can notice how in neither of those two cases we go through the middle door, if the middle door is imprisonment no matter what answer we gat we won’t go through that one but the freedom ones

Edit: Nailed it! I didn’t do the same order as him but it doesn’t matter. Also I solved this in like 5-10 seconds I’m smart :)

LD-dtsk
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Without watching rest of video here's my solution:
Point to door A and ask "do door A and B lead to freedom?"
If warden answer Yes go through door B (either A or C lead to imprisonment)
If warden answers No go through door C (Door A leads to imprisonment)

sammcewan
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Im glad i figured this one out, since I am not really good in these asking-question-riddles. But I think it would have been better, if you would have presented the logic the other way around:
If the warden says Yes, then door B is safe, regardless if the warden is saying it truthfully or not. Because if he is, then door B is definitly safe. If he chooses randomly then it is also safe to go trough B. If he answers No then you go trough door c with the same logic.
You did showed the Logic correctly, but for me it would made more sense if you switched it around like this. (Sorry for my bad english)

Sem-
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Everyone is saying the warden is evil but it's actually really nice of him to give you at least a 2/3rds chance of walking away free

coreyeverett
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He ain't evil if he offers a chance to escape .. he's just bored lmao

iHawkXJ
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I'm still confused. How does pointing to door A while asking about door B change anything in contrast to pointing to door B or just not pointkng at all? Isn't the warden just going to answer about door B since that's what you asked for? What am I missing?

MeLoener
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I've been stumped by logic puzzles before, but I'm happy to say I was able to work this one out in less than a minute and I didn't even have to break out the pencil and paper. My thought process was, "would pointing to a door and asking if it led to freedom help? No? What about pointing to a door and asking if _another_ door would lead to freedom?" Then it was just a matter of playing through all of the scenarios.

Phlebas