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Best Answer DeGe, 23 October 2013 - 10:10 AM

Spoiler for slightly better

Spoiler for Optimising Kukupai's solution for M
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#1 BMAD

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Posted 18 October 2013 - 04:26 PM

**Risking the chastisement of repeating another forum question**
 
 
Samwise Gamgee has a square plot of land, each side being 1 unit. One day, Sam finds out that the dark Lord Sauron has a telephone line that he uses to speak with a traitor amongst the hobbits.
 
Gandalf informs him that the telephone line runs in a straight line parallel to the ground and passes beneath the square plot of land, but he does not know its location. Sam decides to dig up around the perimeter of his land to discover the telephone line, but Gandalf says it is not necessary to dig around the entire length of 4 units.
 
Sam brightens up, and says "I know what you mean. I can just dig 3 sides and still discover it. For even if the phone line runs along the fourth side, I will still detect it at the end points ! "
 
Gandalf shakes his head. "No, Sam. You are on the right track, but you can do better than that."
 
What solution does Gandalf have in mind for the optimum length of the "digging curve" ?

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#2 DeGe

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Posted 18 October 2013 - 05:16 PM

Spoiler for Possibility


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#3 dgreening

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Posted 18 October 2013 - 05:22 PM

Spoiler for One approach

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#4 dgreening

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Posted 18 October 2013 - 05:23 PM

Spoiler for Possibility

I agree, we were working in parallel.


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#5 DeGe

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Posted 21 October 2013 - 08:31 AM

Spoiler for Better than before


Edited by DeGe, 21 October 2013 - 08:32 AM.

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#6 BMAD

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Posted 21 October 2013 - 11:02 PM

Should we be digging the inside of the shape?


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#7 kukupai

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Posted 23 October 2013 - 12:08 AM

Spoiler for slightly better


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#8 DeGe

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Posted 23 October 2013 - 10:10 AM   Best Answer

Spoiler for slightly better

Spoiler for Optimising Kukupai's solution for M

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#9 dgreening

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Posted 24 October 2013 - 09:13 PM

 

Spoiler for slightly better

Spoiler for Optimising Kukupai's solution for M

 

very elegant solution(s)! My hat is off to both of you!


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