Riad Khanmagomedov's April Contest — 23rd to 29th April 2021
Administrator
Subject: Riad Khanmagomedov's April Contest — 23rd to 29th April 2021 @ 2021-03-17 9:07 PM (#29007) (#29007) Top


2000100010020
Location: India

April Contest


This annual contest shall take place from 23-29 April 2021.
More details shall be shared in April 2021.

Administrator
Subject: Re: Riad Khanmagomedov's April Contest — 23rd to 29th April 2021 @ 2021-04-23 8:58 AM (#29169 - in reply to #29007) (#29169) Top


2000100010020
Location: India

Test duration


The test starts on [April 23] 1200 hrs Moscow Standard Time (GMT [April 23] 0900 hrs / IST [April 23] 1430 hrs).

Submissions close on [April 29] 2359 hrs Moscow Standard Time (GMT [April 29] 2059 hrs / IST [April 30] 0230 hrs ).

Administrator
Subject: Re: Riad Khanmagomedov's April Contest — 23rd to 29th April 2021 @ 2021-04-23 10:46 AM (#29170 - in reply to #29007) (#29170) Top


2000100010020
Location: India

Contest page


The Puzzle Booklet shall be uploaded just before the start of the contest at the Contest page: https://logicmastersindia.com/live/?contest=M202104Contest

Administrator
Subject: Re: Riad Khanmagomedov's April Contest — 23rd to 29th April 2021 @ 2021-04-23 10:52 AM (#29171 - in reply to #29169) (#29171) Top


2000100010020
Location: India

Some notes about April Contest 2021

Please note this contest will have a slightly different format than regular LMI tests.

Key differences from regular LMI tests:
1. There is no IB (i.e. no Instructions Booklet). If you have any questions about any puzzle, please ask here in the forum.
2. The PB (Puzzle Booklet) does not have any password.
3. You can download the pdf and start solving. Login at the contest page and click on "Start test" to start submitting.
4. There is no time limit. You can submit until the contest ends.
5. There will be some optimizer puzzles. Other puzzles will be very hard (compared to regular LMI tests)
6. Same scores will have same rank (i.e. early submissions do not count towards rank)

Other important points:
7. There shall be no instant grading in this test.
8. There shall be no online solving interface (like penpa) provided for this test.
9. The score page shall be made available later.
10. There shall be 9 pages in the Puzzle Booklet.
11. Participants can submit answers any number of times. The last submission shall be considered for scoring.
12. There shall be no separate notification on submitting answers.

pankh
Subject: Re: Riad Khanmagomedov's April Contest — 23rd to 29th April 2021 @ 2021-04-23 4:30 PM (#29173 - in reply to #29007) (#29173) Top




Posts: 1

In Puzzle 8, Sudoku without sums, The sums in circles cannot be repeated on any shown line or in any 3x3 box. Does that mean that the number of circle should not match any number in the line or in 3x3 box? Or is it restricted only to the sums in circles?
Timjamiller
Subject: Re: Riad Khanmagomedov's April Contest — 23rd to 29th April 2021 @ 2021-04-23 6:42 PM (#29174 - in reply to #29007) (#29174) Top




Posts: 27
20
Location: USA
For Opti-Names, can the same letter be used consecutively? For example, if a name was JERRY, would it require one R or two?
Riad Khanmagomedov
Subject: Re: Riad Khanmagomedov's April Contest — 23rd to 29th April 2021 @ 2021-04-24 12:00 AM (#29175 - in reply to #29173) (#29175) Top


Moscow Puzzle Cup 2016 Author

Posts: 168
100202020
Location: Russia
pankh - 2021-04-23 4:30 PM

In Puzzle 8, Sudoku without sums, The sums in circles cannot be repeated on any shown line or in any 3x3 box. Does that mean that the number of circle should not match any number in the line or in 3x3 box? Or is it restricted only to the sums in circles?

The sums in circles cannot be repeated on any shown line and the sums in circles cannot be repeated in any 3x3 box.
Riad Khanmagomedov
Subject: Re: Riad Khanmagomedov's April Contest — 23rd to 29th April 2021 @ 2021-04-24 12:02 AM (#29176 - in reply to #29174) (#29176) Top


Moscow Puzzle Cup 2016 Author

Posts: 168
100202020
Location: Russia
Timjamiller - 2021-04-23 6:42 PM

For Opti-Names, can the same letter be used consecutively? For example, if a name was JERRY, would it require one R or two?

You can take two letters R for one R.
kiwijam
Subject: Re: Riad Khanmagomedov's April Contest — 23rd to 29th April 2021 @ 2021-04-24 8:39 AM (#29177 - in reply to #29007) (#29177) Top




Posts: 164
100202020
Location: New Zealand
Hi Riad,

1. Sudokuscope: Is this correct?: a number cannot be the average of the two adjacent cells in the same ring, and cannot be the average of the two adjacent cells in the same sector.
Does the example have another solution? e.g. Horizontal line is 2143,2143, vertical line is (the same) 4231,4231.

2. Akari With Mirrors: Both sides of every mirror should be lit?

4. Bubbles: Does the example have another solution? e.g. The centre bubble can move one cell right.

7. Pentomining: The example shows the solution twice.

8. Sudoku Without Sums: I am checking that "shown line" means "black line". e.g. In the puzzle there is a circle in column 1, between rows 2 and 3. The sum in this circle must be different to (a) the two other circles in column 1, or (b) the four other circles between row 2 and row 3?

Thanks.
kheti
Subject: Re: Riad Khanmagomedov's April Contest — 23rd to 29th April 2021 @ 2021-04-24 9:39 AM (#29179 - in reply to #29007) (#29179) Top




Posts: 11

Location: India
Hi,

For the Sudoku with sums, the example solutions do not match the columns highlighted. 1st and 2nd column are highlighted but solution shows 1st and 4th column.

Thanks.
Riad Khanmagomedov
Subject: Re: Riad Khanmagomedov's April Contest — 23rd to 29th April 2021 @ 2021-04-24 2:07 PM (#29180 - in reply to #29177) (#29180) Top


Moscow Puzzle Cup 2016 Author

Posts: 168
100202020
Location: Russia
kiwijam - 2021-04-24 8:39 AM

Hi Riad,

1. Sudokuscope: Is this correct?: a number cannot be the average of the two adjacent cells in the same ring, and cannot be the average of the two adjacent cells in the same sector.
Does the example have another solution? e.g. Horizontal line is 2143,2143, vertical line is (the same) 4231,4231.

2. Akari With Mirrors: Both sides of every mirror should be lit?

4. Bubbles: Does the example have another solution? e.g. The centre bubble can move one cell right.

7. Pentomining: The example shows the solution twice.

8. Sudoku Without Sums: I am checking that "shown line" means "black line". e.g. In the puzzle there is a circle in column 1, between rows 2 and 3. The sum in this circle must be different to (a) the two other circles in column 1, or (b) the four other circles between row 2 and row 3?

Thanks.

Hi James,

1. In your solution, there is a region with a bold border that contains 2 twice.

2. Yes.

4. You're right, I'll fix the example.

7. Thanks, I'll fix the example.

8. Only (b).
Riad Khanmagomedov
Subject: Re: Riad Khanmagomedov's April Contest — 23rd to 29th April 2021 @ 2021-04-24 2:10 PM (#29181 - in reply to #29179) (#29181) Top


Moscow Puzzle Cup 2016 Author

Posts: 168
100202020
Location: Russia
kheti - 2021-04-24 9:39 AM

Hi,

For the Sudoku with sums, the example solutions do not match the columns highlighted. 1st and 2nd column are highlighted but solution shows 1st and 4th column.

Thanks.

Thank you, I will correct the text.
Administrator
Subject: Re: Riad Khanmagomedov's April Contest — 23rd to 29th April 2021 @ 2021-04-24 11:33 PM (#29182 - in reply to #29007) (#29182) Top


2000100010020
Location: India

Updated Puzzle Booklet


A new Puzzle Booklet has been published at 11:30 PM IST (9:00 PM Moscow Standard Time) on 24 April.

Changes:
1) Puzzle 4 - Example fixed
2) Puzzle 7 - Example fixed
8) Puzzle 8 - Example Answer key value corrected

kheti
Subject: Re: Riad Khanmagomedov's April Contest — 23rd to 29th April 2021 @ 2021-04-26 12:04 AM (#29183 - in reply to #29007) (#29183) Top




Posts: 11

Location: India
For Akari with mirrors, are cells which the light from a lamp visits after reflecting from a mirror, also considered to be lit? The rule isn't very clear on this point.

Also, for half cells, do both sides of the mirror have to be lit or is it okay if only one side is lit?

Thanks,
Nikhil
kheti
Subject: Re: Riad Khanmagomedov's April Contest — 23rd to 29th April 2021 @ 2021-04-26 1:40 PM (#29185 - in reply to #29007) (#29185) Top




Posts: 11

Location: India
Hi,

For the Chain Puzzle (#9), some parts of a fragment are moving anti-clochwise in a circle and other parts are moving clockwise in another circle. For e.g., the red fragment of length 3 at the top left, it is moving anti-clockwise in the quarter of the top left circle and clockwise in the 2 quarters of the next circle.

How is the clockwise and anti-clockwise movement considered for this puzzle?

Thanks,
Nikhil
Swagatam
Subject: Re: Riad Khanmagomedov's April Contest — 23rd to 29th April 2021 @ 2021-04-26 9:23 PM (#29186 - in reply to #29183) (#29186) Top




Posts: 40
2020
Location: India
kheti - 2021-04-26 12:04 AM

For Akari with mirrors, are cells which the light from a lamp visits after reflecting from a mirror, also considered to be lit? The rule isn't very clear on this point.

Also, for half cells, do both sides of the mirror have to be lit or is it okay if only one side is lit?

Thanks,
Nikhil


Lamps lit the cells even after reflecting from a mirror.

For half cells, I considered both sides of a mirror has to be lit.
Riad Khanmagomedov
Subject: Re: Riad Khanmagomedov's April Contest — 23rd to 29th April 2021 @ 2021-04-27 12:55 AM (#29187 - in reply to #29185) (#29187) Top


Moscow Puzzle Cup 2016 Author

Posts: 168
100202020
Location: Russia
kheti - 2021-04-26 1:40 PM

Hi,

For the Chain Puzzle (#9), some parts of a fragment are moving anti-clochwise in a circle and other parts are moving clockwise in another circle. For e.g., the red fragment of length 3 at the top left, it is moving anti-clockwise in the quarter of the top left circle and clockwise in the 2 quarters of the next circle.

How is the clockwise and anti-clockwise movement considered for this puzzle?

Thanks,
Nikhil

It doesn't really matter.
kheti
Subject: Re: Riad Khanmagomedov's April Contest — 23rd to 29th April 2021 @ 2021-04-27 10:01 AM (#29188 - in reply to #29007) (#29188) Top




Posts: 11

Location: India
Hi Riad,

I am more concerned about the rule "When moving
clockwise, the lengths of these fragments must alternate in the sequence 1-2-3-1-2-3...1-2-3". How do I read when it is moving clockwise and when anti-clockwise?

Thanks,
Nikhil
Riad Khanmagomedov
Subject: Re: Riad Khanmagomedov's April Contest — 23rd to 29th April 2021 @ 2021-04-28 1:02 AM (#29194 - in reply to #29188) (#29194) Top


Moscow Puzzle Cup 2016 Author

Posts: 168
100202020
Location: Russia
kheti - 2021-04-27 10:01 AM

Hi Riad,

I am more concerned about the rule "When moving
clockwise, the lengths of these fragments must alternate in the sequence 1-2-3-1-2-3...1-2-3". How do I read when it is moving clockwise and when anti-clockwise?

Thanks,
Nikhil

Hi Nikhil,
You can simplify it: in one direction along the chain, the lengths of the fragments alternate in the sequence 1-2-3-1-2-3, and in the reverse 3-2-1-3-2-1...
kheti
Subject: Re: Riad Khanmagomedov's April Contest — 23rd to 29th April 2021 @ 2021-04-28 8:42 AM (#29200 - in reply to #29186) (#29200) Top




Posts: 11

Location: India
Thanks Swagatam.
kheti
Subject: Re: Riad Khanmagomedov's April Contest — 23rd to 29th April 2021 @ 2021-04-28 8:43 AM (#29201 - in reply to #29194) (#29201) Top




Posts: 11

Location: India
Thanks Riad
kheti
Subject: Re: Riad Khanmagomedov's April Contest — 23rd to 29th April 2021 @ 2021-04-28 6:37 PM (#29205 - in reply to #29007) (#29205) Top




Posts: 11

Location: India
Hi Riad,

For the chains puzzle (#9), is there a missing black dot on the shown fragment of the circle in row 6, column 5?

Most likely, I made a mistake somewhere and broke the puzzle but just wanted to check.

Thanks,
Nikhil
Administrator
Subject: Re: Riad Khanmagomedov's April Contest — 23rd to 29th April 2021 @ 2021-04-28 9:37 PM (#29206 - in reply to #29205) (#29206) Top


2000100010020
Location: India

Contest Submissions


There will be no extension of the submission time for this contest.
Participants should ensure that the submissions are completed before 2400 hrs Moscow Standard Time on the 29th of April.

forcolin
Subject: Re: Riad Khanmagomedov's April Contest — 23rd to 29th April 2021 @ 2021-04-30 4:00 AM (#29218 - in reply to #29007) (#29218) Top





Posts: 167
100202020
Location: Italy
another great contest, thanks Riad
kiwijam
Subject: Re: Riad Khanmagomedov's April Contest — 23rd to 29th April 2021 @ 2021-04-30 4:53 AM (#29219 - in reply to #29007) (#29219) Top




Posts: 164
100202020
Location: New Zealand
Yes, thank you Riad for these great new ideas and interesting optimisers. (and that 14-point Sudoku was so hard!)
Administrator
Subject: Re: Riad Khanmagomedov's April Contest — 23rd to 29th April 2021 @ 2021-04-30 6:17 AM (#29220 - in reply to #29007) (#29220) Top


2000100010020
Location: India

Optimizer Submissions

Submissions to Optimizer puzzles here.

Puzzle 10 and 12 are not checked for uniqueness. If you notice any incorrect submissions, please help Riad by reporting them.

SP1
Subject: Re: Riad Khanmagomedov's April Contest — 23rd to 29th April 2021 @ 2021-04-30 11:30 AM (#29224 - in reply to #29007) (#29224) Top




Posts: 8

Location: Japan
Great contest, Riad!!!
After the contest, I found that there was an typo in my submit of P11......
(R4C5 N -> W) I'm so sorry about this error.

Edited by SP1 2021-04-30 12:00 PM
Riad Khanmagomedov
Subject: Re: Riad Khanmagomedov's April Contest — 23rd to 29th April 2021 @ 2021-04-30 4:16 PM (#29227 - in reply to #29224) (#29227) Top


Moscow Puzzle Cup 2016 Author

Posts: 168
100202020
Location: Russia
SP1 - 2021-04-30 11:30 AM

Great contest, Riad!!!
After the contest, I found that there was an typo in my submit of P11......
(R4C5 N -> W) I'm so sorry about this error.

Thank you Takuma, Stefano, James and all the participants for the nice reviews!

OK, when checking, I inserted W instead of N.

Also, Mihailich wrote to me that in his answer to Puzzle 12, the black cell should be CP, not CI. I took note of that, too.


Edited by Riad Khanmagomedov 2021-04-30 4:17 PM
Administrator
Subject: Re: Riad Khanmagomedov's April Contest — 23rd to 29th April 2021 @ 2021-04-30 4:54 PM (#29228 - in reply to #29227) (#29228) Top


2000100010020
Location: India
Riad Khanmagomedov - 2021-04-30 4:16 PM
Also, Mihailich wrote to me that in his answer to Puzzle 12, the black cell should be CP, not CI. I took note of that, too.

There were similar problems for OlgaShut, Christian, Jo97 as well. Instead of column I, the black cell was put in column P. This is fixed now.

Updated link to Optimizer submissions
Mihalich
Subject: Re: Riad Khanmagomedov's April Contest — 23rd to 29th April 2021 @ 2021-04-30 7:18 PM (#29230 - in reply to #29007) (#29230) Top




Posts: 24
20
Location: Ukraine
Address to the organizers of the answer form.
My decision on the puzzle 11 is gone! Decisions were sent several times and corrected, but in the end there was nothing left!
Please accept for consideration if possible my last submitted version
11. OPTI-NAMES 13 DZ1GLJ2 FUO1AT2 PH1V1I1N SC1X1E1M WYK1BR.


Edited by Mihalich 2021-04-30 7:18 PM
Mihalich
Subject: Re: Riad Khanmagomedov's April Contest — 23rd to 29th April 2021 @ 2021-04-30 7:38 PM (#29231 - in reply to #29007) (#29231) Top




Posts: 24
20
Location: Ukraine
Riad, thank you for a very interesting and powerful task!!!
Once again, your tasks are original again!
Riad Khanmagomedov
Subject: Re: Riad Khanmagomedov's April Contest — 23rd to 29th April 2021 @ 2021-04-30 8:00 PM (#29232 - in reply to #29231) (#29232) Top


Moscow Puzzle Cup 2016 Author

Posts: 168
100202020
Location: Russia
Mihalich - 2021-04-30 7:38 PM

Riad, thank you for a very interesting and powerful task!!!
Once again, your tasks are original again!

Thank you Vladimir,
All your answers are accepted and included in the updated booklet.
Riad Khanmagomedov
Subject: Re: Riad Khanmagomedov's April Contest — 23rd to 29th April 2021 @ 2021-04-30 8:00 PM (#29233 - in reply to #29007) (#29233) Top


Moscow Puzzle Cup 2016 Author

Posts: 168
100202020
Location: Russia
Preliminary results have been announced.
Congratulations to Takuma, Ken and James!

Edited by Riad Khanmagomedov 2021-04-30 8:01 PM
SP1
Subject: Re: Riad Khanmagomedov's April Contest — 23rd to 29th April 2021 @ 2021-04-30 8:30 PM (#29234 - in reply to #29227) (#29234) Top




Posts: 8

Location: Japan
Riad Khanmagomedov - 2021-04-30 4:16 PM

SP1 - 2021-04-30 11:30 AM

Great contest, Riad!!!
After the contest, I found that there was an typo in my submit of P11......
(R4C5 N -> W) I'm so sorry about this error.

Thank you Takuma, Stefano, James and all the participants for the nice reviews!

OK, when checking, I inserted W instead of N.

Also, Mihailich wrote to me that in his answer to Puzzle 12, the black cell should be CP, not CI. I took note of that, too.


Thank you Riad!
And I'm very happy to get 1st place!!!
sergi
Subject: Re: Riad Khanmagomedov's April Contest — 23rd to 29th April 2021 @ 2021-04-30 9:03 PM (#29235 - in reply to #29007) (#29235) Top




Posts: 1

Location: Russia
Is the best solution in puzzle 11 correct?
Riad Khanmagomedov
Subject: Re: Riad Khanmagomedov's April Contest — 23rd to 29th April 2021 @ 2021-05-01 12:14 AM (#29236 - in reply to #29235) (#29236) Top


Moscow Puzzle Cup 2016 Author

Posts: 168
100202020
Location: Russia
sergi - 2021-04-30 9:03 PM

Is the best solution in puzzle 11 correct?

I checked puzzles 10 and 12, and puzzle 11 was checked by the Deb program. Now I see that Christian repeated some letters in the solution. It is necessary to change the points, but this will not change the place in the top three.
Thank you for your comment!
debmohanty
Subject: Re: Riad Khanmagomedov's April Contest — 23rd to 29th April 2021 @ 2021-05-01 7:29 AM (#29237 - in reply to #29236) (#29237) Top



1000500100100100202020
Location: India
Riad Khanmagomedov - 2021-05-01 12:14 AM

sergi - 2021-04-30 9:03 PM

Is the best solution in puzzle 11 correct?

I checked puzzles 10 and 12, and puzzle 11 was checked by the Deb program. Now I see that Christian repeated some letters in the solution. It is necessary to change the points, but this will not change the place in the top three.
Thank you for your comment!
Like Christian and panista, I also missed the rule that letters cannot be repeated. Have uploaded the revised submissions.
kiwijam
Subject: Re: Riad Khanmagomedov's April Contest — 23rd to 29th April 2021 @ 2021-05-01 7:51 AM (#29238 - in reply to #29007) (#29238) Top




Posts: 164
100202020
Location: New Zealand
Great optimizing solutions by Takuma and Nikola!
andsoldat
Subject: Re: Riad Khanmagomedov's April Contest — 23rd to 29th April 2021 @ 2021-05-01 4:20 PM (#29240 - in reply to #29007) (#29240) Top




Posts: 1

Location: Russia
Puzzle Solutions please
Nikola
Subject: Re: Riad Khanmagomedov's April Contest — 23rd to 29th April 2021 @ 2021-05-02 12:25 AM (#29241 - in reply to #29240) (#29241) Top


Sudoku Day Author

Posts: 98
20202020
Location: Serbia
Thank you Riad for keeping the continuity of the former Diogen contest, i miss it a lot. That was the time when I entered the puzzle world.

Thanks, James! The optimizers were sweet and small enough to start working again.

Congartualtions to the top solvers!
vjain9
Subject: Re: Riad Khanmagomedov's April Contest — 23rd to 29th April 2021 @ 2021-05-05 2:08 PM (#29251 - in reply to #29007) (#29251) Top




Posts: 36
20
Location: India
Enjoyed the tough puzzles. Please do share the Solutions please