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#26 2012-06-02 20:02:07

bob bundy
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Registered: 2010-06-20
Posts: 6,269

Re: Who lives in the city

hi Stefy,

When I started this I got 3 solutions.

http://www.mathisfunforum.com/viewtopic … 63#p220263

post #3

The other day I got 2 solutions!

I hope the wording has been changed because, if not, I'm going senile.

I shall sit down with a clean sheet and re-work this today and see what I get this time.

My 'method' is (i) copy the constraints into Word and (ii) start a spreadsheet.

As I 'use' each constraint I hide it by changing the colour of the text to white.

When I cannot force any more entries I switch to red on my spreadsheet, make several copies, and try out the possibilities.

When I'm done with all possibilities I unhide the constraints and check them against my 'solutions' to make sure I've only got answers that fit everything.

Bob


You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei

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#27 2012-06-02 20:08:35

anonimnystefy
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From: The Foundation
Registered: 2011-05-23
Posts: 14,883

Re: Who lives in the city

That is what I am worried about. I want to see what phrontister has come up with, check that, and, if all his solutions are okay, I will try finding a new clue based on that. Then I can check it on whatever you get.

I think this is the most trouble a logic puzzle has given me,apart from anna_gg's flour puzzle. smile

Stefy


“Here lies the reader who will never open this book. He is forever dead.

“Taking a new step, uttering a new word, is what people fear most.” ― Fyodor Dostoyevsky, Crime and Punishment

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#28 2012-06-02 22:53:02

bob bundy
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Registered: 2010-06-20
Posts: 6,269

Re: Who lives in the city

hi

I've re-worked the original version (without the new rule) and got four solutions, not just three as I has in

http://www.mathisfunforum.com/viewtopic … 63#p220263

I have put them below in a screen shot.

The new rule doesn't, unfortunately, lead to a single solution, as I had thought due to missing one solution before.  Sorry.

Instead of "The 21-year-old is next to Eilish", I suggest "The person who watches the Simpsons doesn't live in a town."

I believe that narrows it to a single answer with Amy living in the city.

Bob

View Image: who lives in the city v3.gif

You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei

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#29 2012-06-02 23:10:43

anonimnystefy
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Re: Who lives in the city

What about:"The person watching the neighbors is next to Eilish" instead of my proposed clue?


“Here lies the reader who will never open this book. He is forever dead.

“Taking a new step, uttering a new word, is what people fear most.” ― Fyodor Dostoyevsky, Crime and Punishment

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#30 2012-06-03 01:13:44

bob bundy
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Posts: 6,269

Re: Who lives in the city

Yes,could be that.  I thought mine had an interesting negative twist to it.

Or for an added twist:

"Amy is not 81".

This leaves three solutions, but they all have the same answer to the question "Who lives in the city?"

Bob


You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei

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#31 2012-06-03 01:21:40

anonimnystefy
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Re: Who lives in the city

That would be interesting,but defeats the Einstein puzzles which is to get a solution without any guessing and should have only one and unique solution.


“Here lies the reader who will never open this book. He is forever dead.

“Taking a new step, uttering a new word, is what people fear most.” ― Fyodor Dostoyevsky, Crime and Punishment

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#32 2012-06-03 04:16:07

bob bundy
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Posts: 6,269

Re: Who lives in the city

But the question is "Who lives in the City?" not "Try to find out all the details of the five people".

The solution would be unique!

Bob


You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei

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#33 2012-06-03 04:17:23

anonimnystefy
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Re: Who lives in the city

I haven't seen either questions anywhere in the text.


“Here lies the reader who will never open this book. He is forever dead.

“Taking a new step, uttering a new word, is what people fear most.” ― Fyodor Dostoyevsky, Crime and Punishment

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#34 2012-06-03 07:03:05

phrontister
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From: The Land of Tomorrow
Registered: 2009-07-12
Posts: 3,819

Re: Who lives in the city

Hi,

Here's a set of questions that I think gives a unique solution...with no guesswork required:-

1. The person in the middle watches Desperate Housewives   
  2. Bob is the first in the queue                                                                                            
  3. The person who watches the Simpsons is next to the person who lives in a youth hostel
  4. The person going to Africa is behind Rachael
  5. The person who lives in a village is 52
  6. The person who is going to Australia has straight hair
  7. The person travelling to Africa watches Desperate Housewives
  8. The 14-year-old is at the end of the queue
  9. Amy watches Eastenders                                                                                           
10. The person heading to Italy has long hair
11. Keeley lives in a village                                                                                           
12. The 46-year-old is bald                                                                                           
13. The fourth in the queue is going to England
14. The people who watch Desperate Housewives and Neighbours are standing next to each other
15. The person who watches Coronation Street stands next to the person with an afro
16. A person next to Rachael has an afro
17. The 21-year-old lives in a youth hostel
18. The person who watches Corrie has long hair
19. The 81-year-old lives on a farm                                                                                           
20. The person who is travelling to France lives in a town
21. Eilish is not next to the person with straight hair

There are two changes to the clues that are on the puzzle page:
1. Clue #14 becomes "The people who watch Desperate Housewives and Neighbours are standing next to each other", instead of "The people with curly and straight hair are standing next to each other".
2. Clue #21 added.

The way I solved it discovers who lives in the city well before the end, with the last answer being a choice between the two ages 21 and 81, depending on the finishing solution path.

Last edited by phrontister (2012-06-03 07:58:48)


"The good news about computers is that they do what you tell them to do. The bad news is that they do what you tell them to do." - Ted Nelson

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#35 2012-06-03 07:09:49

anonimnystefy
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Re: Who lives in the city

But we needn't change any clues.Either way,I think those few propositions will be enough for MIF to choose.


“Here lies the reader who will never open this book. He is forever dead.

“Taking a new step, uttering a new word, is what people fear most.” ― Fyodor Dostoyevsky, Crime and Punishment

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#36 2012-06-03 07:13:48

phrontister
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From: The Land of Tomorrow
Registered: 2009-07-12
Posts: 3,819

Re: Who lives in the city

Yes, it's up to MathsIsFun. I'm just happy to have found a set of clues that gives a unique solution. smile

As far as I know, the clues below are the original ones, which have already been changed:-

* The person in the middle watches Desperate Housewives
* Bob is the first in the queue
* The person who watches the Simpsons is next to the person who lives in a youth hostel
* The person going to Africa is behind Rachael
* The person who lives in a village is 52
* The person who is going to Australia has straight hair
* The person travelling to Africa watches Desperate Housewives
* The 14-year-old is at the end of the queue
* Amy watches Eastenders
* The person heading to Italy has long hair
* Keeley lives in a village
* The 46-year-old is bald
* The fourth in the queue is going to England
* The people with curly and straight hair are standing next to each other
* The person who watches Coronation Street stands next to the person with an afro
* The person next to Rachael has an afro
* The 21-year-old lives in a youth hostel
* The person who watches Corrie has long hair
* The 81-year-old lives on a farm
* The person who is travelling to France lives in a town

Last edited by phrontister (2012-06-03 07:21:37)


"The good news about computers is that they do what you tell them to do. The bad news is that they do what you tell them to do." - Ted Nelson

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#37 2012-06-03 07:31:28

anonimnystefy
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Posts: 14,883

Re: Who lives in the city

I was saying that the change of the clue #14 doesn't need changing.


“Here lies the reader who will never open this book. He is forever dead.

“Taking a new step, uttering a new word, is what people fear most.” ― Fyodor Dostoyevsky, Crime and Punishment

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#38 2012-06-03 08:06:19

phrontister
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From: The Land of Tomorrow
Registered: 2009-07-12
Posts: 3,819

Re: Who lives in the city

Hi stefy,

Some clue changes were needed to be made in order to obtain a unique solution, and I chose #14 (in conjunction with the additional clue #21) to achieve that.

In doing so, I tried to retain the flavour of the puzzle setter's wording.

What is the full set of clues, including an unaltered #14, that you think will give a unique solution? (it's probably up above somewhere). And have you solved it yourself?

Last edited by phrontister (2012-06-03 08:12:43)


"The good news about computers is that they do what you tell them to do. The bad news is that they do what you tell them to do." - Ted Nelson

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#39 2012-06-03 08:14:55

anonimnystefy
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Registered: 2011-05-23
Posts: 14,883

Re: Who lives in the city

anonimnystefy wrote:

What about:"The person watching the neighbors is next to Eilish" instead of my proposed clue?

Bob also gave his two or three propositions.


“Here lies the reader who will never open this book. He is forever dead.

“Taking a new step, uttering a new word, is what people fear most.” ― Fyodor Dostoyevsky, Crime and Punishment

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#40 2012-06-03 08:18:46

bob bundy
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Registered: 2010-06-20
Posts: 6,269

Re: Who lives in the city

hi Stefy and phrontister,

I've been checking post #34.  That works for me.  Let's go with it and we can move on.


Thanks,

Bob


You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei

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#41 2012-06-03 08:26:55

anonimnystefy
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From: The Foundation
Registered: 2011-05-23
Posts: 14,883

Re: Who lives in the city

I think we should leave MIF to decide.He has enough options.

Just one question-are you sure that each proposition gives a unique solution?


“Here lies the reader who will never open this book. He is forever dead.

“Taking a new step, uttering a new word, is what people fear most.” ― Fyodor Dostoyevsky, Crime and Punishment

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#42 2012-06-03 08:28:26

phrontister
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From: The Land of Tomorrow
Registered: 2009-07-12
Posts: 3,819

Re: Who lives in the city

Hi stefy,

I was out all day yesterday, and having had it in mind during the day to do what I did with the clue changes, I didn't even check earlier posts but blindly went ahead with my idea. That all took enough time to get right, and by the time I finished it I forgot to go back and check your posts.

Sorry about that.


"The good news about computers is that they do what you tell them to do. The bad news is that they do what you tell them to do." - Ted Nelson

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#43 2012-06-03 08:32:48

anonimnystefy
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From: The Foundation
Registered: 2011-05-23
Posts: 14,883

Re: Who lives in the city

It's okay. I don't mind. And it seems Bob doesn't either. It is just important that we improve MIF as much as we can. smile

Do you have any puzzles similar to the "Little people" puzzle?


“Here lies the reader who will never open this book. He is forever dead.

“Taking a new step, uttering a new word, is what people fear most.” ― Fyodor Dostoyevsky, Crime and Punishment

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#44 2012-06-03 08:50:11

phrontister
Real Member
From: The Land of Tomorrow
Registered: 2009-07-12
Posts: 3,819

Re: Who lives in the city

anonimnystefy wrote:

Do you have any puzzles similar to the "Little people" puzzle?

No, not really. There are some others that you can play in a group where you need to watch (or listen to) what the other person is doing and try to work out what's going on. No clues given...like in LP (you know I wasn't really giving you clues when we played that...I was just leading you on smile ).

So in these other games you just have to suss it out from what's happening. No good over the internet, though, cos it needs live participation. And I'd rather not try to explain them.


"The good news about computers is that they do what you tell them to do. The bad news is that they do what you tell them to do." - Ted Nelson

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#45 2012-06-03 08:52:37

anonimnystefy
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From: The Foundation
Registered: 2011-05-23
Posts: 14,883

Re: Who lives in the city

I don't understand. Can you explain the principle of the game a little?


“Here lies the reader who will never open this book. He is forever dead.

“Taking a new step, uttering a new word, is what people fear most.” ― Fyodor Dostoyevsky, Crime and Punishment

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#46 2012-06-03 08:58:35

phrontister
Real Member
From: The Land of Tomorrow
Registered: 2009-07-12
Posts: 3,819

Re: Who lives in the city

Hi MIF, Bob and stefy,

Here's my solution to post #34...plus my worksheet.

I'm pretty sure that the solution is unique, because during the solution process no alternative paths that I could follow popped up...unlike all other versions I've tried.

View Image: Who lives in the city - solution.png View Image: Who lives in the city.png

Last edited by phrontister (2012-06-03 09:29:35)


"The good news about computers is that they do what you tell them to do. The bad news is that they do what you tell them to do." - Ted Nelson

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#47 2012-06-03 09:03:32

anonimnystefy
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From: The Foundation
Registered: 2011-05-23
Posts: 14,883

Re: Who lives in the city

What is the stuff you used shown in the 2nd pic?


“Here lies the reader who will never open this book. He is forever dead.

“Taking a new step, uttering a new word, is what people fear most.” ― Fyodor Dostoyevsky, Crime and Punishment

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#48 2012-06-03 09:12:59

phrontister
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From: The Land of Tomorrow
Registered: 2009-07-12
Posts: 3,819

Re: Who lives in the city

I'm not sure what you mean.

I basically use the method Bob does (see his post #26), but I like to use individual colours to help me keep track better, particularly with a puzzle this size.

The magazine puzzles (usually much smaller than this one) are done just with pen and paper, of course. With ticks and crosses.


"The good news about computers is that they do what you tell them to do. The bad news is that they do what you tell them to do." - Ted Nelson

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#49 2012-06-03 09:14:30

anonimnystefy
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From: The Foundation
Registered: 2011-05-23
Posts: 14,883

Re: Who lives in the city

What is the software you used to get that second picture? I.e. Where di you write all the clues and stuff?


“Here lies the reader who will never open this book. He is forever dead.

“Taking a new step, uttering a new word, is what people fear most.” ― Fyodor Dostoyevsky, Crime and Punishment

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#50 2012-06-03 09:24:20

phrontister
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From: The Land of Tomorrow
Registered: 2009-07-12
Posts: 3,819

Re: Who lives in the city

I used an Excel spreadsheet. The puzzle wording and clues are just direct copy/pastes from the MIF puzzle page (although I did some re-sizing to make things fit onto one page).

All the other coloured boxes are just typical spreadsheet cells that I coloured as I went along with the solution, using colours instead of ticks and crosses. Those cells started out white.


"The good news about computers is that they do what you tell them to do. The bad news is that they do what you tell them to do." - Ted Nelson

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