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Country : India | Logic Masters India announces Qixi Festival Special Sudoku Test.
Date - 14th, 15th and 16th August (Yes, 72 hours since Qixi Festival falls on 16th August )
Sudoku Types - Classic Relays (1~8 ), Match Makers (9~16 ), Qixi Special Twin Sudoku
Length - 120 minutes
Submission Link : http://logicmastersindia.com/M201008S2
The IB is very interesting read and everyone should check it out.
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Ziti
Posts: 42
Country : United States | Ziti posted @ 2010-08-05 2:02 AM I have a question about the Match Makers puzzles. Let's say a certain puzzle has all different digits on the diagonal but *also* is nonconsecutive. Does that mean I did something wrong? I am not sure if the rules say that each puzzle must have only *one* extra rule or not.
(I realize it will probably be the case that only one extra rule will work for each individual puzzle, but I thought I should ask anyhow.)
This looks like great fun! Wow, August is loaded up with great puzzles!
JZ |
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debmohanty
Country : India | We had a set of Matchmakers in Mock17
If I remember correctly, one had to first identify the rule for one specific grid. But a casual look at some grids, it was not obvious what the rule could be.
Lets wait till we hear from LeafCard about the Matchmakers in this set.
Yes, we are having more tests than usual in August. This is mainly due to we are gearing up for IPC (on 12th Sep )
Before IPC we'll have at least 2 more Puzzle (non-Sudoku ) tests as well.
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Leaf Card
Posts: 9
Country : China | reply for Ziti:
maybe the match mode is not same as before, i wrote "Maybe you can find some situations corresponded for more than one rules. Then you should consider other situation and rule’s combination." the form in the IB have unique solution that every row and column have only one "true", and you can find the solution by logic. i think the form is another "sudoku".
can you understand? |
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purifire
Posts: 460
Country : India | Leaf Card - 2010-08-05 1:27 PM
reply for Ziti:
maybe the match mode is not same as before, i wrote "Maybe you can find some situations corresponded for more than one rules. Then you should consider other situation and rule’s combination."
can you understand?
So Leafcard, If I understand correctly you mean to say that if Puzzle A has the features of a Diagonal sudoku and it so happens that all numbers are non-consecutive, and if Puzzle B has all the features of a Non-consecutive sudoku, then we are supposed to treat Puzzle A as a Diagonal Sudoku??
I hope my question makes some sense. : )
Rishi |
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Fred76
Posts: 337
Country : Switzerland | Fred76 posted @ 2010-08-05 4:42 PM Wow, an 8-grids match makers ! Already with 6 grids it's not obvious.
We must "have eyes in front of holes" (translation of a french expression )  ,
and above all be comfortable with the 8 types of grid.
Fred |
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Fred76
Posts: 337
Country : Switzerland | Fred76 posted @ 2010-08-05 4:47 PM I think the point is:
A single puzzle can be treated as, say, nonconsecutive or diagonal, with different solution. But there is only one way to solve 8 grids and that each rule correspond a single puzzle.
If a puzzle A can be treated as nonconsecutive AND diagonal and a puzzle B can be only treated as diagonal, the puzzle A has to be solved as a nonconsecutive !
Am I correct?
Fred |
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Leaf Card
Posts: 9
Country : China | i got purifire's idea, "puzzle A 's solution is diagonal and also non-consecutive", it won't happen.
when you try to correspond one rule to one situations, for example: if r2c2=1, r1c4=1, then it can't be no knight step sudoku, or some advance logic method to make the form unique.
Fred have a good explanation for the rule, thank you!
Edited by Leaf Card 2010-08-05 4:59 PM
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purifire
Posts: 460
Country : India | Ok I get it, so each puzzle will follow only one constraint and if in my solution I get a diagonal and a non-consecutive, then obviously there is a mistake that I have made somewhere..... :)
I hope this clarifies Jason's question as well. :)
Rishi |
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debmohanty
Country : India | Adding my 2¢s -
There will be exactly one way in which the 8 instructions will fit in with the 8 grids. One needs to use the table in page 6 to keep track of all the eliminations.
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vopani
Posts: 739
Country : India | vopani posted @ 2010-08-06 12:02 AM In the Classic Relays, the transfer of digits from one puzzle to the next one can be in any order, right? (If R1C2 is shaded in both puzzles, it is NOT NECESSARY that they should have the same number, correct? But it should have one of the three numbers in the shaded cells of the first puzzle)? |
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debmohanty
Country : India | Rohan Rao - 2010-08-06 12:02 AM
In the Classic Relays, the transfer of digits from one puzzle to the next one can be in any order, right? (If R1C2 is shaded in both puzzles, it is NOT NECESSARY that they should have the same number, correct? But it should have one of the three numbers in the shaded cells of the first puzzle)?
Yes, that how it looks like from the IB. |
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purifire
Posts: 460
Country : India | Rohan Rao - 2010-08-06 12:02 AM
In the Classic Relays, the transfer of digits from one puzzle to the next one can be in any order, right? (If R1C2 is shaded in both puzzles, it is NOT NECESSARY that they should have the same number, correct? But it should have one of the three numbers in the shaded cells of the first puzzle)?
Thats Correct Rohan... Elimination by sudoku rules has to be used to determine which number goes into which cell.... say a number 4 in R1C2 may or may not be in RiC2 of second puzzle depending how the clues are placed in puzzle 2. This is assuming that R1C2 is shaded in both puzzles : ) |
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Administrator
Country : India | Announcement
We found that the grey cell marks and the dotted cell marks may not be distinguished clearly in paper print-outs
The authors have changed them to white circles and grey circles. Check the updated IB.
There are no other differences.
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Administrator
Country : India | Announcement - About Sudoku#17
Sudoku# 17 is a twin sudoku (Classic + Irregular having same solution ) . However, it does not have any givens. After solving Puzzle 1 to 16, you have to copy 20 digits to Sudoku#17 and start solving.
Our online flash interface will not do the copying for you. If you are planning to solve online, copying these digits from other grids might not be efficient because lot of scrolling will be involved.
So, we are providing the grid for Sudoku#17 now itself. Click here to download
We think this will be very handy while copying the digits from other grids. Online solvers are suggested to keep a print out ready of this page.
[ This page will also be part of the puzzle booklet, so paper players don't have to do anything now. Of course, they can check out the grid and find some tricks :-)]
If you have any questions, please post here. |
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rakesh_rai
Posts: 774
Country : India | Can you check the jigsaw borders once...I think there is one mistake in the pdf (in the last row, most probably) |
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Administrator
Country : India | Notes for online solvers
There are 8 Matchmakers Sudokus.
It is not possible to show all the 8 Matchmakers in the submission site at one time because of computer screen size.
From Mock17 experience, we think it is becomes easier when you can see all the Sudokus together.
If that is the case with you, you may want to solve the matchmakers on paper.
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Administrator
Country : India | rakesh_rai - 2010-08-10 10:41 AM
Can you check the jigsaw borders once...I think there is one mistake in the pdf (in the last row, most probably)
please be specific... I can't see the problem.
Note that sometimes when Acrobat Reader is not at 100% zoom, it may not show some images perfectly. Try to zoom out and see.
But if that is the case, there won't be any problem while printing.
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rakesh_rai
Posts: 774
Country : India | OK. Let me be specific...One jigsaw area has 10 cells and another has 8 cells. |
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Administrator
Country : India | Further note on Sudoku#17
There will be obviously 2 grids.
1) The flash system is not equipped to automatically copy digits from each other.
2) While submitting, submitting any of the grid is fine.
If some player submits both the grids, and non-zero digits don't match, he/she will get 0.
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purifire
Posts: 460
Country : India | Administrator - 2010-08-10 10:22 AM
Announcement - About Sudoku#17
Sudoku# 17 is a twin sudoku (Classic + Irregular having same solution ) . However, it does not have any givens. After solving Puzzle 1 to 16, you have to copy 20 digits to Sudoku#17 and start solving.
If you have any questions, please post here.
The grid for puzzle seventeen has numbers 1 to 20, which I assume will be the clues to be transferred. but will the same numbering be used in the actual puzzles too for transfer? |
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Administrator
Country : India | rakesh_rai - 2010-08-10 10:56 AM
OK. Let me be specific...One jigsaw area has 10 cells and another has 8 cells.
Ouchh... Disabled downloading of the file until the error is fixed. |
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purifire
Posts: 460
Country : India | As has been informed.... classic 8 and the matchmakers will have cells marked with numbers 1 to 20 which need to be transferred to puzzle 17 to solve it. |
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Gotroch
Posts: 83
Country : Czech Republic | Gotroch posted @ 2010-08-10 2:40 PM Is it possible to solve classic puzzles in relay without transfering digits? |
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debmohanty
Country : India | Gotroch - 2010-08-10 2:40 PM
Is it possible to solve classic puzzles in relay without transfering digits?
I'm not sure if I understand your question properly.
Here is how it will work.
CR = Classic Relay
CR1 will have 4 cells with grey circles. CR2 will have 4 cells white circles.
After solving CR1, you need to transfer the digits in these 4 grey circles to the 4 white circles in CR2.
CR2 will have 4 cells with grey circles. CR3 will have 4 cells white circles.
After solving CR2, you need to transfer the digits in these 4 grey circles to the 4 white circles in CR3.
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So on
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CR7 will have 4 cells with grey circles. CR8 will have 4 cells white circles.
After solving CR7, you need to transfer the digits in these 4 grey circles to the 4 white circles in CR8.
CR8 will not have any grey circles.
Hope that clarifies.
Gotroch - 2010-08-10 2:40 PM
Is it possible to solve classic puzzles in relay without transfering digits? If you don't transfer the digits from CR1 to CR2, you will find multiple solutions to CR2.
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Gotroch
Posts: 83
Country : Czech Republic | Gotroch posted @ 2010-08-10 4:14 PM debmohanty - 2010-08-10 3:39 PM
If you don't transfer the digits from CR1 to CR2, you will find multiple solutions to CR2.
Thanks, this is all I need to know.
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Administrator
Country : India | |
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Minfang Lin
Posts: 40
Country : China | You can determine digits' position by logic, don't worry about this.
It's the first time we do this kind of relay, so they're easy to determine, eg: {1234} from previous puzzle, and in next puzzle the mark cell already have {123} in its peer cells, so this cell must be 4.
but, no all like this :) if you make the wrong place, you will find no solution for the puzzle, or if you haven't decide all marked cells, you will find multiple solution.
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rakesh_rai
Posts: 774
Country : India | I went through the IB version 2 but could not find the points distribution. When is the points distribution expected to be announced? |
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Administrator
Country : India | |
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Minfang Lin
Posts: 40
Country : China | Another notice for players: Please make a table for variants part before the test, or print the one in extra page. |
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Minfang Lin
Posts: 40
Country : China | |
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Administrator
Country : India | !!! Best of luck to everyone !!! |
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Fred76
Posts: 337
Country : Switzerland | Fred76 posted @ 2010-08-14 8:36 PM Hard !!!  |
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purifire
Posts: 460
Country : India | Fred76 - 2010-08-14 8:36 PM
Hard !!!
Oops Fred.... now you are scaring me  |
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vopani
Posts: 739
Country : India | vopani posted @ 2010-08-14 9:24 PM Tough set.
The puzzles were really nice, especially since I like Match-Makers puzzles.
I liked the concept of transfering digits without knowing directly which one goes where, it makes the relay concept more complete :-)
Looking forward to results and feedback of others. |
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debmohanty
Country : India | Rohan, thanks for your comments. Hopefully that will un-scare Rishi. |
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Minfang Lin
Posts: 40
Country : China | Thanks for feedback.
To Fred: i think you can do better.
I hope someone could make Niulang and Zhinv meeting. :-) |
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Fred76
Posts: 337
Country : Switzerland | Fred76 posted @ 2010-08-14 9:49 PM Hard..... but beautiful !
And yes I think I could do better, I've done mistakes !
Fred |
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purifire
Posts: 460
Country : India | debmohanty - 2010-08-14 9:28 PM
Rohan, thanks for your comments. Hopefully that will un-scare Rishi.
Im bad at matchmakers and I dont think anything Rohan said unscares me
You are forgetting that now I am a part time Sudokist... I am not even sure I will be able to take 2 hrs away at a stretch |
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neerajmehrotra
Posts: 329
Country : India | It can never be worse. First did a mistake in Puzzle No 7 and then carried forward the digits to spoil Puzzle No. 8.
In short screwed........... |
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alien2357
Posts: 1
Country : United States | Great set of puzzles. Awfully difficult.
I'm glad I was able to participate this time around. Can't always have 2 hours straight to do puzzles, but when I do, it's always FUN!
Everyone at LogicMastersIndia should be commended. Your mock tests and other puzzle sets are typically high quality stuff. Thanks!
-Allen
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Semax
Posts: 10
Country : Germany | Semax posted @ 2010-08-15 1:28 AM Wow, very nice puzzles. Didn't finish in time but afterwards I have let them meet ;) |
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Gotroch
Posts: 83
Country : Czech Republic | Gotroch posted @ 2010-08-15 6:24 AM Really nice puzzles. 
Matchmaker part was beautiful. |
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rakesh_rai
Posts: 774
Country : India | Overall a nice set of sudokus. The objective was to make Niulang and Zhinv meet, however, both got lost somewhere. The matchmaking logic was beautiful, and unfolded very logically.
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amitsowani
Posts: 349
Country : India | The small point classics were really beautiful and I had never enjoyed solving classic puzzles so much before.
I struggled on the higher point ones, maybe there is something that Im missing in solving the more difficult ones.
Matchmaker was awesome. It was not too difficult to identify which sudoku goes where. The puzzles were high quality too, especially the anti knight sudoku.
I broke the touchy sudoku, else would have had a few more points :(
It might have been better if there were more time to solve, or maybe two separate sections, so that people do not have to choose between which section to solve.
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purifire
Posts: 460
Country : India | Amazing set of puzzles.... thoroughly enjoyed them.... Im not sure how amit and Rohan found match makers easy :D
I wasted nearly 20 mins trying to resolve them... :)
Had a great time solving them nevertheless... |
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Fred76
Posts: 337
Country : Switzerland | Fred76 posted @ 2010-08-15 4:24 PM
I hope someone could make Niulang and Zhinv meeting. :-)
Although my performance was below my abilities, I would not have been able to make Niulang and Zhinv meeting. I'll be surprised if more than 2 people can achieve this goal.
P.S.: I like surprises |
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purifire
Posts: 460
Country : India | Fred76 - 2010-08-15 4:24 PM
I hope someone could make Niulang and Zhinv meeting. :-)
Although my performance was below my abilities, I would not have been able to make Niulang and Zhinv meeting. I'll be surprised if more than 2 people can achieve this goal.
P.S.: I like surprises
I agree with you Fred. |
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skywalker
Posts: 42
Country : Serbia | I had no problem to identify puzzles in matchmaker (7-8 minutes for all eight), but some of them were really hard to solve and I lost a lot of time on them. Classics were as always from Chinese authors, beautiful & tough.
I enjoyed after the test solving puzzles not solved during the test.
Thanks for great puzzles
Branko |
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purifire
Posts: 460
Country : India | skywalker - 2010-08-15 4:45 PM
I had no problem to identify puzzles in matchmaker (7-8 minutes for all eight),
Branko
Wow Branko, That was fast.... It took me 20 mins to identify puzzles in Matchmaker : )
Rishi |
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skywalker
Posts: 42
Country : Serbia | I had only doubts about diagonal and 3 in a row (E/O) after about 5 minutes, but with small guess i resolved that. I was not well prepared for this competition, I haven't seen points table before the contest and I spent most of the time solving some difficult MatchMakers puzzles and not solving classic relay.
But, anyway, excellent and enjoyable test.
Branko |
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vopani
Posts: 739
Country : India | vopani posted @ 2010-08-15 10:54 PM purifire - 2010-08-15 4:02 PM
Amazing set of puzzles.... thoroughly enjoyed them.... Im not sure how amit and Rohan found match makers easy :D
I wasted nearly 20 mins trying to resolve them... :)
Had a great time solving them nevertheless...
I said 'I like Match-Makers', I didn't say 'I found them easy' :P |
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rakesh_rai
Posts: 774
Country : India | Today is the Qixi festival and according to the story Niulang and Zhinv should meet today. For that to happen, someone needs to complete all 17 sudokus today. |
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Ziti
Posts: 42
Country : United States | Ziti posted @ 2010-08-16 2:49 PM This was a wonderful set and a nice treat to celebrate the Qixi Festival. Thank you to everyone responsible for such a great competition! |
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debmohanty
Country : India | For those, who have struggled to match the MatchMakers, Lin Min Fang has prepared a chart on how to match the grids with rules. She will upload soon after the test is over.
I'm sure there will be lot of oohs and aahs after the chart is posted. |
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motris
Posts: 199
Country : United States | motris posted @ 2010-08-16 11:07 PM Very fun (but difficult) competition. Thanks to the organizers. I at least learned this time that I don't need to type in the whole answers but with so much typing at the end I forgot to hit submit on my nonconsecutive :(. Off to finish the last puzzle. |
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KimKing
Posts: 7
Country : Malaysia | KimKing posted @ 2010-08-16 11:15 PM Urgghhh..this one make my brain damaged... |
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jaisbansal
Posts: 6
Country : India | Wonderful Sudokus... couldn't finish the bunch but enjoyed the difficulty level... Looking forward to more :-) |
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Minfang Lin
Posts: 40
Country : China | Thank you for every participant and your feedback, it help us to do better in the future.
We will show you some design idea in Qixi:
First, the classic relay part, please have a look at every puzzle's clues, they're from 20 to 27. but when solve them, you will find they become more and more difficult. In many people's concept, more clues mean much easier. In fact, count of clues and difficulty are not equal. We don't tell you the correct position of every stick digit, but you can determine them by logic. There are many players become puzzle designer, and the process of determine stick digit is also a design, no matter if you had tried design a sudoku, in this test, you had tried. Fulfill the puzzle, then solve it. That's why many players like the classic part. And we also do some thing about this: if you put digits to the wrong place, you will find no solution for the puzzle, or if you haven't decide all marked cells, you will find multiple solution. To the puzzles themselves (i mean when you put all stick digits in right place ), when solve P01 from 1 to 9, you can get all 1, then all 2...all 9, maybe you never find solving sudoku is so happy. P02 - P06 are puzzles can be solved only by singles, but we make them difficulty in observing. P07 - P08 need intersection, pairs and x-wing, they are all basic advance techniques.
To variants match part, at first you will find that you can't solve any number by clues, it's like mock test 11 last year. Then you must determine every situation's rule first, it's mostly like a sudoku, and hints are from eight situation. We make a diagram for you:
(They are all from clues, no guessing or trying to solve one situation for finding a mistake. )
There is a trap in P09, you can try to solve it by diagnol, it has unique solution, but it's a very tough puzzle and you will find another situation don't have rule to correspond. P13 and P15 have the same pattern, it's only for fun :- )
By previous 16 puzzles effort, a "heart" bridge is built. In this twins suoku, you can only solve few cells in single grid, but when make them together (same meaning of "17" in Chinese ), can be solved by single. It also means one need to support others.
At the end, thanks for LogicMastersIndia give us the chance, and all you spend the wonderful Qixi time together.
TTHsieh&Leafcard
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rakesh_rai
Posts: 774
Country : India | Congratulations to the top 20. 600+ in this test is indeed a great score.
I thought that Diagonal should be the easiest variant (as it is the most common variant) but after looking at the results, it (along with Touchy) proved to be the toughest of the lot.
Was the 2-hr timing enough? The scores suggest it was not.
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purifire
Posts: 460
Country : India | rakesh_rai - 2010-08-17 8:05 AM
Was the 2-hr timing enough? The scores suggest it was not.
Looking at scores and when I see that no one including Snyder or Janoslaw could complete it, its evident that 2 hrs was not enough |
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Administrator
Country : India | Congratulations to Jakub Hrazdira, Thomas Snyder, Rodolphe Hurel, Chen Cen and Wu dong yi for topping in LMI Qixi Special Sudoku Test
There were 141 participants out of which 102 got non-zero scores.
Thank you all for participating and making this a success.
Click here for the solution booklet |
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Administrator
Country : India | Sudoku tests take a break now.
Next 2 tests will be Puzzle tests and then we've IPC planned. |
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debmohanty
Country : India | Many thanks to Lin Min Fang and her team for this wonderful set of Sudokus.
I'm sure they have lot of time designing the Sudokus (e.g. in all MatchMaker puzzles it was not possible to solve a single digit without determining its type) [ That probably made it tough :-) and Niulang and Zhinv could not meet )
2:30 hours test would have ensured that at least a couple, if not many, players would have got the bonus points.
Thank you again. |
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rakesh_rai
Posts: 774
Country : India | Deb: Actually, 102 participants got non-zero scores. |
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rakesh_rai
Posts: 774
Country : India | Did anyone manage to get all 8 matchmaker variants correctly ? |
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debmohanty
Country : India | rakesh_rai - 2010-08-17 9:36 AM
Deb: Actually, 102 participants got non-zero scores. Ouchh... Thanks for correcting me. |
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neerajmehrotra
Posts: 329
Country : India | one of the toughest but most interesting competition........
All the puzzles were 5*.. |
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Administrator
Country : India | rakesh_rai - 2010-08-17 9:37 AM
Did anyone manage to get all 8 matchmaker variants correctly ?
2 players (zorko and nikola ) got all the Match Makers correct. [ Interesting that zorko has submitted only one classic ]
janoslaw got 7 correct.
4 more got 6 correct.
As many as 29 players got all Classics correct.
Check here for the split - http://logicmastersindia.com/M201008S2/ScoreSplit.asp
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rakesh_rai
Posts: 774
Country : India | Thanks Deb. So, most participants did not get enough time for matchmakers as only 56 participants got points as against 101 in classics.The testing of the sudokus and the duration of the test could have been better designed. For example, diagonal, touchy, and no three odd/even could have had more points than the rest of the variants. Also, having the test for 2.5 hours is not correct (its too long). We could have dropped one classic and one variation perhaps for a 2 hr test. |
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luckypunk
Posts: 4
Country : India | well..when i completed the classics i found that i had 6 mins left for the variants. :P, i am really slow , i don't know what the standard advanced techniques are...is there some place where i can learn or in that case even the basic ones :P |
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Administrator
Country : India | for some players, Qixi rank is displayed as Qixi Score. This will be fixed soon. Sorry for this inadvertent miss.
thanks to luckypunk for bringing it to our notice. |
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Nikola
Posts: 103
Country : Serbia | Nikola posted @ 2010-08-17 12:11 PM Wonderful sudoku test, congratulations for organizers and all toppers! Classic sudokus are my old complaint, but I think this time I chose the wrong tactics. I have the same number of performed puzzles as Jakub and Thomas, and look at the difference! I solved all matchmaker in about 85 minutes and the rest of time did only 6 classics. |
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jaisbansal
Posts: 6
Country : India | Thanks to Lin Ming Fang.. very logical and definite clues to figure out the match makers :-) |
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Minfang Lin
Posts: 40
Country : China | To luckypunk: you can search "intersection, pairs, x-wing" by google.
To rakesh_rai: diagonal, touchy and no 3 odd/even in line are most difficult in variants part, both the puzzle itself and determining the rule. But if one solved as the order we show, he can complete at least 5/8.
Are there someone need help with the puzzles? Please let us know. All puzzles can be solved by logic. |
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luckypunk
Posts: 4
Country : India | yo thnxs min..got many links...will improve now.. |
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rakesh_rai
Posts: 774
Country : India | MinFang Lin: If you could give a few starting steps on the diagonal (without trial/error ), that'd be helpful. I am stuck at the beginning itself  |
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Minfang Lin
Posts: 40
Country : China | Deb told me about this, maybe your question is many players' question.
i will show you later...please give me some time to do it.
Are there any other questions? |
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Fred76
Posts: 337
Country : Switzerland | Fred76 posted @ 2010-08-17 7:03 PM Thanks for this wonderful tournament, I've just finished to solve grids (I redo the entire relay as it was a catastroph during Test ).
About my test:
I did wonderful stupid mistakes on part I (relay ): Bad report of relay numbers between puzzle 1 and puzzle 2 (I lost about 10 minutes at the very beginning of the test  ). On another relay puzzle, I copy numbers on cells with grey circles instead of cells with white circles .
After 1h10 and finally 7 relay puzzles laboriously finished, I begin "match maker part", it was fun and I manage to solve 5 grids in about 35 minutes (with one mistype - a single digit  - on the antiknight ), which is quite good, I think. Then during the last minutes I try to solve the last relay puzzle, with no success  .
After the test, I finish "match maker part". It was really fun and very good grids. Diagonal was very tough, perhaps too much for this 2h tournament.
grids 17 were fun, too !
I think, inversely to "sampler platter", it was a little bit too difficult for a 2h tournament. Relay are always a trap because you can't do mistakes, otherwise it spreads on next puzzle and you are blocked on every other grids.
Perhaps a 6-grids relay and easier diagonal grid on match maker would have been more balanced for a 2h tournament.
However, it was a very good test with very good grids ! Thanks !
Fred |
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Gotroch
Posts: 83
Country : Czech Republic | Gotroch posted @ 2010-08-17 7:19 PM rakesh_rai - 2010-08-17 6:36 PM
I am stuck at the beginning itself
Transfer square No.16 (row 4, column 5 in the diaonal puzzle ) has only possible digits 2,5,7. Look at final twin puzzle, transfer clues 1 and 14 are digits 7 and 2. So transfer clue 16 has to be 5 and transfer clue 15 is 8 (only possible 8 in irregular shape )
When you add these two digits, diagonal puzzle is easy to complete
Of course, this trick is possible only if you already solve some others matchmaker puzzles before diagonal. Edited by Gotroch 2010-08-17 7:21 PM
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Fred76
Posts: 337
Country : Switzerland | Fred76 posted @ 2010-08-17 7:19 PM there is much of a tie in the standings. Should they not be classified according to the time resolution? |
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debmohanty
Country : India | Fred76 - 2010-08-17 7:19 PM
there is much of a tie in the standings. Should they not be classified according to the time resolution?
Good point Fred. Not sure if we should change anything for this test, because we didn't annouce anything before the test. But in future we must introduce tie-breaker rules.
If others think that we should break the ties based on submission time, we can try to that for this test itself. |
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Fred76
Posts: 337
Country : Switzerland | Fred76 posted @ 2010-08-17 7:26 PM Administrator - 2010-08-17 8:53 AM
Sudoku tests take a break now.
 ! |
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debmohanty
Country : India | Fred76 - 2010-08-17 7:26 PM
Administrator - 2010-08-17 8:53 AM
Sudoku tests take a break now.
!
And with that post, this thread becomes the thread-with-most-posts at LMI forum |
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Minfang Lin
Posts: 40
Country : China | The first step of diagonal:
See D\ only two place can be 7 (r1c1 and r5c5 ), so r1c9 and r9c1 can't be 7.
Then check D/ only one cell can be 7, it's r5c5. |
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Minfang Lin
Posts: 40
Country : China | |
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rakesh_rai
Posts: 774
Country : India | Thanks Min. After that crossover step, it does indeed solve out logically. |
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neerajmehrotra
Posts: 329
Country : India | debmohanty - 2010-08-17 7:25 PM
Fred76 - 2010-08-17 7:19 PM
there is much of a tie in the standings. Should they not be classified according to the time resolution?
Good point Fred. Not sure if we should change anything for this test, because we didn't annouce anything before the test. But in future we must introduce tie-breaker rules.
If others think that we should break the ties based on submission time, we can try to that for this test itself.
It will become easy buddy when you spend some time and give the total time till the submission of last answer in minutes instead of time of submission..... |
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Ziti
Posts: 42
Country : United States | Ziti posted @ 2010-08-18 2:22 AM I am happy to see others found the Diagonal to be difficult. I spent many minutes trying to find that first number and simply couldn't find it for quite some time! But once I did I was able to make some progress -- it still was not easy from that point forward however.
The crossover step is perfectly legitimate, and I think this is one of the best Diagonal puzzles I've ever solved. Like many others on the test, it is 5-star.
When it comes to ties -- I'm reminded of the 2009 Semifinals where a time-based tiebreaker for incomplete solutions was used, and it did not seem to work out very fairly. If two great solvers did exactly the same puzzles and didn't finish, maybe they both deserve the credit? |
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Fred76
Posts: 337
Country : Switzerland | Fred76 posted @ 2010-08-18 3:27 AM When it comes to ties -- I'm reminded of the 2009 Semifinals where a time-based tiebreaker for incomplete solutions was used, and it did not seem to work out very fairly. If two great solvers did exactly the same puzzles and didn't finish, maybe they both deserve the credit?
I was not in Zilina, but I think it's a very different situation. Here you have not to choose stop playing before end of time. You can submit answer before the end of test and continue to try to solve last puzzles.
if two great solver who didn't finish have same amount of points, but one reached it after 1h45 and the second after 1h58, it seems fair to me that the first one appears first in the ranking.
I don't say it's not fair now, it's just a detail, not very important for the LMI tests. |
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motris
Posts: 199
Country : United States | motris posted @ 2010-08-18 3:39 AM For diagonal sudoku, I've quite often found visualizing placements along the extra constraint, such as at WSC2 Prague Final and here, incredibly valuable. Indeed, so much so that I specifically take time in my solving routine to think about the immediate consequences of any number much more so than any other variant, kind of like a Nishio where you see if a few placements down the way you can possibly place all 9 instances of a digit with exactly 1 on each diagonal. This is generally not useful on classics, since a lot of either/or choices in empty space don't do much, but on diagonals the difference between two options is often digits on 0 diagonals, or 2 digits on a single diagonal, or other results that can't work. So I would not say I was looking for a crossover here (I'm not familiar with the term actually). But one of the first things I did was convince myself R1C1 couldn't be a 4. Similar thinking next showed me the 7 couldn't be in that spot either, so one or the other had to be in the center and that became obvious as the 7 (leaving R2C2 for the 4). That's just how my mind approaches diagonals. And I guess I suspected by then, since no Matchmaker could have any digits placed without identifying the extra constraint, that some cool diagonal cycle was certainly the way to start the puzzle here. |
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motris
Posts: 199
Country : United States | motris posted @ 2010-08-18 3:52 AM Re: Zilina and tiebreaking - the fundamental problem in Slovakia was not grading playoff puzzles along the way, as has been done by virtually all other WPC/WSC hosts in my time competing. Having 36 semifinalists in a single heat made this impractical, but that's a whole other discussion about good/bad planning decisions.
Within your scoring system, you have time-stamps for when a solver has submitted their last "correct" solution which makes it clear when, at a particular score, solvers have reached that point. Imagine a close test that has a grossly undervalued puzzle that is a particular stumper for many people. Maybe no one solves it, maybe someone does. But if 3-4 people are tied without just that puzzle, then the first to have everything but that one solved is a very fair tiebreaker to use. Here, Jakub and I are still pretty close to tied within 2 minutes (not a terribly meaningful amount of time to separate us, but I'd pip him out), but anything approaching a 10-15 minute separation case, as was the case in Zilina, would have let a large number of tied solvers be separated fairly. There, many solvers reached 3 of 4 puzzles done with 10+ minutes left to attempt the last stumper. Slower solvers who eventually reached 3 of 4 puzzles done with 2 minutes on the clock just said done and turned in their papers since they had no chance to finish the last puzzle. Since you'll know when solvers get to a particular score, its not a comparable situation.
As one of the most vocal critics of competition rules, I'd be completely satisfied with using the last submitted time as a sorting method with granularity at 1 minute levels pretty reasonable to view as a tie break.
Edited by motris 2010-08-18 4:02 AM
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Ziti
Posts: 42
Country : United States | Ziti posted @ 2010-08-18 5:32 AM Using the timestamp of the final correct puzzle is certainly not an unfair way to break ties. I don't think anybody would have a claim that they deserved to be ranked higher *because* they didn't submit until after the other person.
But when there are still puzzles yet to be solved, there are other reasons why someone could be "ahead" (which is to say they solved all but one puzzle more quickly than anyone else). If you are done with *all* your puzzles (and you solved on paper), then you immediately submit them electronically. But if you have one puzzle left...maybe you spend as much time as you think you can on that puzzle? Maybe you leave five minutes at the end of the test to transfer your paper solutions over to the website, so while it seems like you just then solved the second-to-last puzzle, really you reached that point many minutes before and were just stuck.
If this tiebreaker were adopted, since players from all over the world value LMI tests as the top monthly sudoku competitions, they would naturally want to rank as high as possible. But I think that would mean they would go from paper-to-computer-to-paper-to-computer...over and over near the end of the testing period, which is just when they need to focus the most on solving. I think that's needlessly inefficient and doesn't really reflect who's better.
I would prefer weighting the puzzles themselves *slightly* differently. Give an extra 0.1 to the hardest puzzle, 0.01 to the second-hardest, 0.001 to the third-hardest...and so on. So if you match someone's point total, maybe these fractional points will provide the difference. Or, in the case where nobody finishes the test, let the top performers stay tied. |
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Minfang Lin
Posts: 40
Country : China | I'm in Zilina too. By the rule of round 2, i came to add-round, more than 70 players had same score with me. Maybe after that, many players use the rule to get previous rank. I think it's not fair to top players, maybe they only use 20 mins to finish 3/4, but the fourth puzzle is very very hard. Other players maybe use 30 mins to finish 3/4, if they submit first, they come to next round.
Online competition is different too, we can't know if one is still working on the puzzles after last submitting. If base on last submitting, it will be more unfair.
I had thought if it's necessary to make every variant in different points, as Ziti said, i can give diagonal 56 pts, and maybe non-consecutive 54 pts. But they are all 55 pts. Because it's unlike with classic, everyone will be good at different type of variants. If your are good at one variant but it has a low score, you will feel unfair to you. And see once again with the diagram, many players maybe didn't find P14 can't be no 3 odd/even, then diagonal, touchy, no 3 odd/even are last remain puzzles. As you see, the hardest step in diagonal is the first step, so i think one will give up this puzzle when he can't find any step.
Edited by Minfang Lin 2010-08-18 6:57 AM
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Minfang Lin
Posts: 40
Country : China | To Thomas:
Do you know the technique Finned X-Wing, Empty Rectangle and ... they are alike nishio, and i think they are good and interesting techniques.
Every variant has its own special technique, and the designer should show it in his puzzle.
To Ziti and others (I'm sure you will like the logic ):
Find the next step of this diagonal sudoku:
(Hint: check digit 9 ) |
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debmohanty
Country : India | neerajmehrotra - 2010-08-17 9:55 PM
It will become easy buddy when you spend some time and give the total time till the submission of last answer in minutes instead of time of submission.....
Neeraj, Sorry it took longer than I thought I would take because of other commitments. But finally I've done it (2 weeks? after you suggested )
Updated score page - http://logicmastersindia.com/M201008S2/score.html
I've added 2 more columns -
LastCSub - stands for - last Correct Submission
TimeTillLCS - stands for - Time Taken till Last Correct Submission
Examples (for whom LastSub and LastCSub are different )
Gotroch : 6 minutes after he submitted the last correct puzzle, he just submitted P09 without filling anything.
Rohan Rao : 25 minutes after he submitted the last correct puzzle, he just submitted P09, which turned out to be wrong.
Many other examples are there. But I just choose top 2 for illustration.
The table is now sorted by Total Points Descending, then by TimeTillLCS Ascending.
However, I've not modified the Ranks yet, since players are having different opinion about using LastCSub as a tie-breaker rule.
I tend to agree with Ziti, when he mentions that paper players would be at a disadvantage since they might have to do paper-to-computer-to-paper-to-computer...over and over near the end of the testing period.
Lets wait for few more voices before we take a decision. |
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motris
Posts: 199
Country : United States | motris posted @ 2010-08-18 9:01 AM Very nice example Minfang. When I'm solving sudoku for fun I often run into eliminations like Finned X-Wing or Empty Rectangle which are very much what I'd just call situational thinking - like a Nishio with two steps ahead - but are pretty powerful to catch. When I'm solving classic sudoku for speed though, I rarely reach a stage where I'm searching for any of those things and on hard puzzles I will admittedly bifurcate with underlined digits to see if I can force a solution onto a grid. I'll also use uniqueness and other things that I wouldn't use when just solving logically.
To Ziti: Solving on paper versus online is a choice applied to all solvers evenly (choosing paper means you wait for it to print, but get the advantage of any notes you want, ...). Solvers can do some on paper and some online. Its the solver's option. So I don't think its necessarily unfair to apply a time-based standard that might require paper solvers to enter their answer with say 30 minutes left instead of at the last second, provided the value of time is made clear ahead of time. For this test, I entered all the relays and five of the matchmakers with ~25 minutes left, figuring I should get those pages entered, and then simply came back two more times to enter the last. Of course I missed one submit button (on the easiest respective "nonconsecutive" puzzle), but that's beside the point. I'd say you and others would use a similar strategy on the USPC - at some point after 2 hours make sure your answers are in place and then start trying to pick off 1 at a time. This approach - certainly with solvers knowing how tiebreaks apply - seems like one can adapt how they'd play on paper to not be disadvantaged.
Its also true that the matchmakers weren't evenly difficult, so changing their scores a little would help. More important is probably increasing the relative score of the matchmakers versus the classic relay as the classic relay was certainly a much higher point/minute value than the other which is why I started there. Solvers like Nikola that finished the whole Matchmaker were somewhat hurt scoring-wise by the relative valuation, although different scores for that section would certainly affect my strategy and likely others' as well.
Edited by motris 2010-08-18 9:06 AM
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Administrator
Country : India | Administrator - 2010-08-17 11:17 AM
for some players, Qixi rank is displayed as Qixi Score. This will be fixed soon. Sorry for this inadvertent miss.
thanks to luckypunk for bringing it to our notice.
This is fixed now (hopefully correctly ) |
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Minfang Lin
Posts: 40
Country : China | To Thomas:
We called the method like this "magic step". I think all the top players have their own magic method.
Because many people only play classic puzzles, they don't know how to solve variants, and everyone want to get a better score, everyone will be happy when he get a higher score. It's a relay, so later puzzles also have extra points for all correct previous puzzles. Nikola and zorko did best in matchmaker, i think they can get 100 pts more for the great job. And Nikola show us another method for diagonal, it's also great. |
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Minfang Lin
Posts: 40
Country : China | Amit said: The small point classics were really beautiful and I had never enjoyed solving classic puzzles so much before.
So we make 3 "small point" classics (solved from 1 to 9 ), but you should find the correct position of digits from previous puzzles first.
Just enjoy them!
000210000003000100060004020020000007006105300800000040070400090001000500000032000
000000600010304000600010000000900000009000500000002000000030006020105030004000700
003200000070000430040010005000500006000000100100006000900000020050000070000000300
TTHsieh&Leafcard Edited by Minfang Lin 2010-08-18 5:41 PM
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rakesh_rai
Posts: 774
Country : India | Minfang Lin - 2010-08-18 9:52 AM
Nikola and zorko did best in matchmaker, i think they can get 100 pts more for the great job. So, does Nikola move to 790...and, into first place... |
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amitsowani
Posts: 349
Country : India | Thanks for these additional puzzles Minfang Lin.
By low points classics I had meant the first four, so apart from the first one which went from 1 to 9, I liked the next three too :)
Good work with the increasing number of givens. Though I did not notice it during the test, this is the perfect way to display that the difficulty is not directly related to the number of initial clues.
The hard work that you guys have put in making the puzzles is evident from the quality of puzzles. Thanks a lot.
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vopani
Posts: 739
Country : India | vopani posted @ 2010-08-18 8:27 PM debmohanty - 2010-08-18 8:42 AM
However, I've not modified the Ranks yet, since players are having different opinion about using LastCSub as a tie-breaker rule.
I tend to agree with Ziti, when he mentions that paper players would be at a disadvantage since they might have to do paper-to-computer-to-paper-to-computer...over and over near the end of the testing period.
Lets wait for few more voices before we take a decision.
Lets not change the ranks for this test. We can start from next time if this works out. |
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amitsowani
Posts: 349
Country : India | Thanks for all the feedback regarding the tie breaking rules.
Ziti had pointed out that the paper players have a disadvantage if we now use the last correct submission time as a tie breaker. Motris also suggested that it would not be a disadvantage if the tie breaker rules are announced before the test.
Going forward we will use the last correct submission for breaking ties between players.
However since we had not announced the rules prior to the Qixi event we will not change the rankings. |
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