Puzzle for you guys!!!!

gopunk

Lifer
Jul 7, 2001
29,239
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i'm doing discrete structures hw, and there are some cool puzzles on it. this is NOT one of them... there was a problem with a part A and part B. we were assigned the part A, and now i am showing you guys part B.


Four friends have been identified as suspects for an unauthorized access into a computer system. They have made statements to the investigating authorities. Alice said "Carlos did it." John said "I did not do it." Carlos said "Diana did it". Diana said "Carlos lied when he said that I did it".

If the authorities also know that exactly one is lying, who did it? Explain your reasoning.
 

PlatinumGold

Lifer
Aug 11, 2000
23,168
0
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Alice said "Carlos did it." John said "I did not do it." Carlos said "Diana did it". Diana said "Carlos lied when he said that I did it".

Simple

Carlos is lying, everyone else is telling the truth, therefore.

Alice (truth) Carlos did it.

John (truth) I did not do it.

Carlos (lie) Diana did it.

Diana (truth) Carlos lied when he said that i did it.

hence carlos did it according to alice who was telling the truth.
 

PlatinumGold

Lifer
Aug 11, 2000
23,168
0
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carlos, because alice says he did it and so does diana

actually diana doesn't explicitly say that carlos did it, only that carlos lied about her doing it.

it requires alices additional truthful statement to nail down who actually did it.

the other way of looking at it is, alice and diana confirm that carlos is lying.
 

TonyG

Platinum Member
Feb 12, 2000
2,021
2
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Hmm, I am thinking that Diana did it, because the statements would have been made privately with each individual to the officer taking the statements, if I am not correct? If so, Diana did it, because how would she have known that Carlos said that she did it?

Make any sense at all, or am I just really tired and talking out of know where?
 

gopunk

Lifer
Jul 7, 2001
29,239
2
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Originally posted by: TonyG
Hmm, I am thinking that Diana did it, because the statements would have been made privately with each individual to the officer taking the statements, if I am not correct? If so, Diana did it, because how would she have known that Carlos said that she did it?

Make any sense at all, or am I just really tired and talking out of know where?

uh....... this is special land..... where cops interrogate groups all at once..... :D
 

Demon-Xanth

Lifer
Feb 15, 2000
20,551
2
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Carlos, he was a butler and everyone knows the butler did it!


Alice said carlos did it.
Carlos said Diana did it. So either Alice or Carlos is lying.
Diana said Carlos lied. So either Diana or Carlos is lying.

Assuming only one is lying, John is taken out by the fact that two other people were fingered, Alice and Diana cannot be it since if one was lieing, so would the other.
 

PlatinumGold

Lifer
Aug 11, 2000
23,168
0
71
Hmm, I am thinking that Diana did it, because the statements would have been made privately with each individual to the officer taking the statements, if I am not correct? If so, Diana did it, because how would she have known that Carlos said that she did it?

Make any sense at all, or am I just really tired and talking out of know where?

sorry, wrong answer, this is purely a logic question and not an interogation logistic question.

if diana did do it and lie than alice's statement would also have been a lie making the initial PREMISE (that only one person lied) incorrect.

so on pure logic alone, carlos lied and other did not.

 

TonyG

Platinum Member
Feb 12, 2000
2,021
2
81
Hmm, figured I was wrong, its what I get for trying to look at these type of problems at midnight.
 

Francodman

Diamond Member
Dec 11, 1999
4,965
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Of course they blame the hispanic
rolleye.gif
;)
 

Havoc13

Senior member
Jun 16, 2000
571
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Originally posted by: Demon-Xanth


John is taken out by the fact that two other people were fingered,

The real question is, who got fingered?

and if you say Freddy I'll smack ya... :)