Some people asked me about the order of the puzzles; in the set of leftover-puzzles, there are other combinations than in the IB. For example: 'Minimax' has the same given digits as 'Maximin' in the leftover puzzles, but in the IB 'Minimax' has the same givens as 'Chaos Diagonal' and 'Maximin' has the same givens as 'Consecutive'.

The combination of puzzles in the real test will be the same as in the IB. They also will be in the same order as in the IB.

About Equal Sudoku : do you have more practice materials?
I don't remember seeing this type anywhere.

Since this is indeed a new type (as far as I know) AND it is the puzzle with the most points, I decided to make one other practise puzzle. I published it in the puzzle portal of Logic Masters Germany. You can find it here: Equal III

Of course there are the two ohter Equal puzzles from an earlier message in this thread: In message
#7556 there is a large list of practise material where you can find under E)
7 Equal medium medium

These three puzzles should give solvers the opportunity to get used to the type.

So will there be bonus points for people who clone/copy-paste their scores from last weekend?

That wouldn't work, you'd create a paradox. Because if they'd get bonus points, then the scores wouldn't be equal anymore and they wouldn't be entitled to the bonus anymore, so it would have to be dropped again.

I thought of that a while after posting. Award the bonus points in the next month then :P

Edited by prasanna16391 2012-07-06 11:09 AM

I really enjoyed this set. I shall name my favorites later, but all the grids had nice solving paths.

On a personal note, I think I've finally come out of my slump of making 5+ errors everytime. Luck's as always not on my side though, with printer issues and all that, but overall quite happy with my performance considering recent ones.

Thanks Richard.

I enjoyed the puzzles !

About partial bonus : Please note that partial bonus is not automatically computed, it needs some manual intervention. So after finishing, players may not see partial bonus being added to the score immediately, but eventually the score will be adjusted.

Beautiful puzzles!

Prasanna, anurag, tamz: Thanks!
As an author it's as important that the puzzles are well appreciated as it is to see good scores!

Since I made less mistakes while solving than last week, I had to make a typo in the codes... A matter of equilibrium I guess.

Anyway, nice set of puzzles; some of them were even better than nice. Thank you Richard.

I always worry with "stunt" tests that the puzzles will suffer from the extra constraint. In this case, there was no need to worry. You made a large number of very creative and challenging puzzles. Merci beaucoup!

Interesting copy-paste of the message you posted last week. You are quite in the theme of the test . But I don't understand why you finish your message in french in that case .

Heel erg bedankt !

Maybe he knows that I go to France for holiday most of the years.

Motris, Ours Brun and Fred: thanks for the compliments!

Richard -

My compliments on the well-thought out and symmetrically pleasing puzzles; thanks for the test.

Dave

Copy Paste is over. Congratulations to TiiT, jaku111 and Kota for taking the top 3 positions.

Richard will share his thoughts soon.

First of all: TiiT, jaku111 and Kota: congratulations with the top spots!
Amazing and impressive results!
All other 258 players: thanks for participating!

I am very delighted with the ratings for the puzzles. Especially for ‘Equal’, although I think it is amazing that it is rewarded 9 times with a score of 10!

Let’s go back to Shapes and Sizes. Based on the results of the test-solvers, I really had the idea back than that a few of the world-top-players would be able to finish all grids. Although it was close, nobody was able to do so. So after the test was over, I did a fair bit of evaluating and came to the conclusion that:
- none of the puzzles on itself was too hard;
- all in all it was too much;
- it lacked a few really easy puzzles, since the list of players who solved only one or two grids was pretty long;
- working with irregular grids was probably the reason for errors by top players and reason for not finishing the complete test. But that’s intrinsic to irregulars.

These conclusions were the ingredients for my second test considering that LMI expects authors to write tests which should be finished by few top players..

About the theme
Since almost five years I make a set of sudoku variants every four weeks for a Dutch/French sudoku magazine for a hobby. The set always contains 4 consecutives. After a while I started to make two different puzzles with the same given digits every now and then. Since the puzzles are published two on a page, I thought it would be nice from an aesthetic point of view to make such a combo once in a while. When I started thinking about a second theme for a LMI-test, this combo-idea crossed my mind pretty soon. Shortly after SaS was over, I suggested this theme to Deb, who was enthusiastic straight away.

I expected it not to be easy, since some of the constraints in the variants are very ‘demanding’. Therefore I chose to use combinations as much as possible where one grid was very ‘demanding’ and the other was much easier to construct. Per page it’s mostly very easy to see which was of the first and which of the latter category.

With the conclusions from SaS in mind I started making the sets of puzzles.
I wanted to compose a set of puzzles that I was able to solve myself in about 2/3 of my own times for SaS. By doing so, I hoped that about 10 players would be able to solve all grids in the test, and lots of players would be able to solve between 5 and 10 grids.

After I finished all 14 sets I decided what puzzles had to be in the IB and, ergo, what had to be in the real test. I wanted to have at least five relatively easy puzzles, a wide range of difficulties and two or three hard puzzles. All test solvers reported that they needed 25% to 35% less total time than for SaS, so that confirmed my feeling this test would be better solved.

I have chosen mainly types that I am familiar with, but wanted to include also a few types that I only made a few times earlier (Minimax and Low) and a completely new type (Equal).

Here are a few words about some of the puzzles:
Chaos Diagonal and Scattered
Unfortunately the puzzles that I liked better from an aesthetic point of view turned out to be too hard for the real test. So they were abandoned to the IB. I wanted one of them to be in the easy category and one in the middle category.

Consecutive
I am really fond of this type. It’s so much fun to work with 5 odd and 4 even digits in a puzzle and having a symbol that says: on either side of me you’ll find one odd and one even digit. For the real test I wanted to make a puzzle with very few circles.

Minimax
For earlier puzzles of this type I didn’t place givens in the grid. It’s not necessary anyway. But with givens and not too many clues outside the grid it was an nice low-pointer.

Ascending
Longer lines provide a fair number of digits to place so that the puzzle solves pretty smoothly after that.

Ascending nonconsecutive
I preferred to use longer lines here too, but the nonconsecutive constraint doesn’t really cooperate. The way to get into this puzzle is of course the grey line in row 5. You can fill in the digits 97531 on that line immediately. After that the two series of 4 digits in rows 3/4 and 6/7 are helpful. Since 1 and 2 cannot be placed in R6C7 and R7C9 you know instantly that the asked order of digits is 3579.

Maximin
For this type you can either work with big differences or with a lot of givens to provide a good start and a smooth solve. One trick that might have been helpful is the series of 3 2’s outside the box top right. This implies that you have to work with the trios 123, 456 and 789. This can be a helpful shortcut to come to sooner placements.

Low
Since I like to work with symmetries this puzzle type gave me a bit of a hard time. I thought it would be nice to use a ‘dice’pattern for one of the puzzles (IB), and connect all grey cells in the other puzzle to give it a nice look.

Position
The corner blocks provide the most info for this type.

Renban
What is very helpful for this puzzle is to notice what digits have to be in a renban group, and what digits cannot be in a group. You can thus place a 3 in R6C9 straight away. Also helpful is that both renban groups starting in R7C2 and in R9C1 need a 6 as well as a 7. In nonet 9 the 6 and 7 are placed somewhere in R8.
Last but not least: two groups that are in a ‘hooked’ pattern cannot contain the same series of digits. There has to be at least one different digit. This rule was very useful in determining the series that started in R1C6 and in R6C9.

Equal
For the test-solvers, Equal was just a bit harder than Renban. But Equal gave players a much harder time than I expected. At least, from what I could see ‘looking behind the screens’.
Very important in this puzzle is to realize that in every cage an even number of odd digits has to be placed. Also in the cages with five cells. In the cage in box 7, a five is included. So the 3 stays out of the cage, giving a sum of 14 (5,9) for three even digits: 2,4,8. The 3 and the 6 go in R9C23.
The cage of four cells in block 1 needs a 4 and a 6.
The cage of three cells in R123C6 needs a 1 since 3,5,8 is not possible.
The most important step is now to realize that the cage of 3 in R6C67 + R7C6 needs a 1. The combination 3,5,8 is not possible, since 8 would go in R6C7 and 3,5 go in R67C6. This blocks both possibilities in the cage of 3 cells in R123C6.
So 1 goes in R6C7.
From here it should run smoothly.

Once again: thanks for participating, and I would really appreciate to read you comments to the test!

Awesome, thats my first one! :)

My favorite was in fact the Equal. I didn't find it hugely difficult, it had a nice solving path. Then come the Renban Groups(although that was one of my mistakes during the contest duration). I really liked the use of row 3/4,5,6/7 as you mentioned in Ascending Nonconsecutive. The Consecutive and Scattered sudoku were among the favorites too.

Thanks again for a fine set of puzzles. :)

So how many times did you refresh the score page? :P

There was a lot of refreshing - It's been a loong weekend for me. That's the result of doing the test on Friday.
In addition, I want to say thanks for the practising material - I solved all of them and It was really useful !!! :)

TiiT

It is always interesting to see new winners. Congratulations!