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Old 2018-10-07, 19:58   #23
a1call
 
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Yes that is true.
So I have wasted my time as well as anyone's who has listened to me.
They have no one to blame but themselves. They should have known better by now.

Last fiddled with by a1call on 2018-10-07 at 20:00
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Old 2018-10-07, 20:35   #24
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So assuming that maximizing the actual number of cells will yield a solution faster, the optimum grid would be L1xL2=5x120=600 with 121x6=726 actual cells.

Last fiddled with by a1call on 2018-10-07 at 20:38
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Old 2018-10-07, 20:44   #25
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Quote:
Originally Posted by a1call View Post
So assuming that maximizing the actual number of cells will yield a solution faster, the optimum grid would be L1xL2=5x120=600 with 121x6=726 actual cells.
You cannot have more than one coordinate with two points present. (Easy to prove. Two simple steps: draw two parallel lines, put two points on each. Now draw triangles and consider their areas. They will form two pairs of equal values.)
Therefore you cannot use L1 or L2 < 9.
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Old 2018-10-07, 21:22   #26
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That is very clever. I had not thought of that. Thank you for the correction.
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Old 2018-10-07, 21:44   #27
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Quote:
Originally Posted by KangJ View Post
Any of two segments cannot be parallel.
You were way ahead of me there pal.
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Old 2018-10-07, 21:46   #28
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Quote:
Originally Posted by Batalov View Post
You cannot have more than one coordinate with two points present. (Easy to prove. Two simple steps: draw two parallel lines, put two points on each. Now draw triangles and consider their areas. They will form two pairs of equal values.)
Therefore you cannot use L1 or L2 < 9.
You also have, that the average of two x (resp. y) coordinates on any perpendicular lines can't be the x or y coordinate of the line it's perpendicular to.
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Old 2018-10-07, 23:28   #29
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Quote:
Originally Posted by Batalov View Post
You cannot have more than one coordinate with two points present. (Easy to prove. <snip>)
Therefore you cannot use L1 or L2 < 9.
KangJ beat you to it here with a more general statement:
Quote:
Any of two segments cannot be parallel.
Same argument applies.
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Old 2018-10-07, 23:58   #30
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Mine was a responce to a specific thing:
Quote:
the optimum grid would be L1xL2=5x120 ...
Yes, I could have just responded - "read the thread". Right?
You think it would have been obvious to the intended audience?

I don't think so. It it was, they wouldn't have written what they have.
Hence, repetition is the mother of learning.
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Old 2018-10-08, 01:20   #31
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A similar mistake I did before (in the above post which I deleted overwrote, I was wondering why the former posters started their lists from 10, haha, then immediately I realized how stupid I was). Of course you can't have parallel lines and moreover, you can't have any symmetric figure (i.e. quadrilateral or higher), either if the symmetry is a dot or a line (the dot symmetry is actually a particular case of parallel lines, but the line symmetry is not, when the line passes through two of the points, think something like a deformed rhombus, or "kite").


Edit: puzzle: how "long" a solution with 10 lines needs to be? (this can be actually "computed" by hand very easy).

Last fiddled with by LaurV on 2018-10-08 at 01:58
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Old 2018-10-09, 14:25   #32
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Found one!
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Old 2018-10-09, 17:34   #33
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Quote:
Originally Posted by Batalov View Post
Found one!
Congrats!!

It has proven to be pretty difficult to go the final inch... but I hope to join you soon.
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