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# Guess 1 out of 100 numbers

18 replies to this topic

### #11 superprismatic

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Posted 06 November 2013 - 02:46 AM

you can have duplicates.

so everyone can be 1 for example.

help me understand this sentence: "Each person receives an anonymous list of 99 numbers representing everyone else's numbers but not her own."

it reads to me, that a person would have a list of numbers that excludes the number they have.

Let's look at a smaller problem with 10 people and integers between 1 and 10 inclusive.  Suppose the 10 numbers given out were 1, 2, 2, 2, 3, 6, 7, 8, 8, and 10.

Further suppose that Mary has been assigned the number 2 (not known to her, of course).  Then Mary would be given the list 1, 2, 2, 3, 6, 7, 8, 8, and 10.  One of the 2s  would be

missing -- one that represents what she has been assigned.  This is the intent of that sentence.

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Posted 06 November 2013 - 06:45 AM

you can have duplicates.

so everyone can be 1 for example.

help me understand this sentence: "Each person receives an anonymous list of 99 numbers representing everyone else's numbers but not her own."

it reads to me, that a person would have a list of numbers that excludes the number they have.

Let's look at a smaller problem with 10 people and integers between 1 and 10 inclusive.  Suppose the 10 numbers given out were 1, 2, 2, 2, 3, 6, 7, 8, 8, and 10.

Further suppose that Mary has been assigned the number 2 (not known to her, of course).  Then Mary would be given the list 1, 2, 2, 3, 6, 7, 8, 8, and 10.  One of the 2s  would be

missing -- one that represents what she has been assigned.  This is the intent of that sentence.

ah ha brilliant. i get it now.

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### #13 phaze

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Posted 07 November 2013 - 06:32 AM

@BMAD I think it also excludes the numbers that nobody has

for 4 people and numbers 1 to 4 a possibility is

Person 1 has  4

1 2 2

Person 2 has 2

1 2 4

Person 3 has 1

2 2 4

Person 4 has 2

1 2 4

due to possible overlap no-one can be certain which number they have.

I think this is what he means by "These numbers are entirely random and independent of one another, meaning there can be duplicates (and consequently missing numbers). "

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Perfecting Mafia suicide since August 2008

### #14 harey

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Posted 07 November 2013 - 09:57 AM

I like the Phil1882 idea of modulo and tried the following rule:

Spoiler for

It works for some examples for N=4 (with no counterexample so far). The next steps should be an exhaustive computer simulation and a strong therie. Someone is willing to continue?

Edited by harey, 07 November 2013 - 09:58 AM.

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### #15 phil1882

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Posted 07 November 2013 - 11:07 AM

close but not quite.

Spoiler for

the true answer for N seems to be

Spoiler for

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### #16 superprismatic

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Posted 03 December 2013 - 06:20 PM

Spoiler for the solution

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### #17 bonanova

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Posted 03 December 2013 - 08:36 PM

Spoiler for the solution

Spoiler for Just to clarify

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Vidi vici veni.

### #18 superprismatic

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Posted 03 December 2013 - 09:20 PM

Spoiler for the solution

Spoiler for Just to clarify

Spoiler for is this what you want to know?

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### #19 bonanova

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Posted 04 December 2013 - 12:04 AM

So I would calculate L and subtract that from my secret number. Cool. Thx.
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Vidi vici veni.

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