Riad Khanmagomedov's April Contest — 15th to 22nd April 2022
@ 2022-04-13 9:52 PM (#30522) (#30522) Top

prasanna16391



Posts: 1604
1000500100
Country : India

prasanna16391 posted @ 2022-04-13 9:52 PM



This annual contest shall take place from 15-22 April 2022.
More details shall be shared in subsequent posts soon.

@ 2022-04-13 9:54 PM (#30523 - in reply to #30522) (#30523) Top

prasanna16391



Posts: 1604
1000500100
Country : India

prasanna16391 posted @ 2022-04-13 9:54 PM

Contest page


The Puzzle Booklet shall be available just before the start of the contest at the Contest page: https://logicmastersindia.com/live/?contest=M202204Contest

@ 2022-04-13 9:56 PM (#30524 - in reply to #30522) (#30524) Top

prasanna16391



Posts: 1604
1000500100
Country : India

prasanna16391 posted @ 2022-04-13 9:56 PM

Some notes about April Contest 2022

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 other than the 1 week duration. 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 10 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.

@ 2022-04-14 9:23 PM (#30525 - in reply to #30522) (#30525) Top

Gotroch



Posts: 81
20202020
Country : Czech Republic

Gotroch posted @ 2022-04-14 9:23 PM

I+am+looking+forward+to+solving+Riad%27s+puzzles%2E+%F0%9F%91%8D%0D%0ABut+for+me+this+contest+would+be+much+better+if+the+first+9+puzzles+had+greater+impact+on+the+results+%28current+format+is+all+about+three+optimizer+puzzles%29%2E%0D%0AI+am+missing+good+old+Puzzle+Marathon+contests%2C+harder+puzzles+like+Riad%27s+would+be+perfect+for+it+and+I+would+enjoy+the+contest+more+if+I+can+compare+myself+with+others+on+all+puzzles%2E
@ 2022-04-14 11:01 PM (#30526 - in reply to #30522) (#30526) Top

Veronika



Posts: 7

Country : Slovakia

Veronika posted @ 2022-04-14 11:01 PM

Looking forward to the puzzles!!
@ 2022-04-14 11:59 PM (#30528 - in reply to #30522) (#30528) Top

prasanna16391



Posts: 1604
1000500100
Country : India

prasanna16391 posted @ 2022-04-14 11:59 PM

The puzzles are available now. All the best to everyone!
@ 2022-04-15 1:07 AM (#30529 - in reply to #30522) (#30529) Top

CJK



Posts: 10

Country : Germany

CJK posted @ 2022-04-15 1:07 AM

Is it allowed to use programs or similar things, especially for the optimization puzzles?
@ 2022-04-15 5:03 AM (#30530 - in reply to #30522) (#30530) Top

YogaRamadhan



Posts: 1

Country : Indonesia

YogaRamadhan posted @ 2022-04-15 5:03 AM

In+the+example+of+puzzle+number+7%2C+Floating+Clouds%2C+it+seems+that+the+2%C3%972+cloud+is+moving+diagonally+from+the+2nd+to+the+3rd+diagram%2E+Is+that+an+error%3F+They+may+only+move+horizontally+and%2For+vertically%2C+i+suppose%2E
@ 2022-04-15 9:12 AM (#30531 - in reply to #30530) (#30531) Top

prasanna16391



Posts: 1604
1000500100
Country : India

prasanna16391 posted @ 2022-04-15 9:12 AM

If they move horizontally "and" vertically that basically results in a possible diagonal movement.
@ 2022-04-15 2:12 PM (#30532 - in reply to #30522) (#30532) Top

Manitary



Posts: 1

Country : Italy

Manitary posted @ 2022-04-15 2:12 PM

In puzzle 2 (Crossroads), in the description is "the line passing through this strip" the straight line segment between the two turns (one for each side of the strip), or the whole line between the two adjacent strips?
@ 2022-04-15 2:53 PM (#30533 - in reply to #30522) (#30533) Top

prasanna16391



Posts: 1604
1000500100
Country : India

prasanna16391 posted @ 2022-04-15 2:53 PM

The former.
@ 2022-04-15 9:16 PM (#30534 - in reply to #30522) (#30534) Top

Aubin Danzo



Posts: 3

Country : France

Aubin Danzo posted @ 2022-04-15 9:16 PM

I have a question about the 3rd Optimizer (the Football one). It is said that a ball cannot cross a circle of the opposite color. But is it possible for the ball to cross a circle of the same color (like if we consider that this player has already got the ball once)?
@ 2022-04-15 11:32 PM (#30535 - in reply to #30534) (#30535) Top

Riad Khanmagomedov



Posts: 187
10020202020
Country : Russia

Riad Khanmagomedov posted @ 2022-04-15 11:32 PM

Aubin Danzo - 2022-04-15 9:16 PM

I have a question about the 3rd Optimizer (the Football one). It is said that a ball cannot cross a circle of the opposite color. But is it possible for the ball to cross a circle of the same color (like if we consider that this player has already got the ball once)?

No, in this case, the ball is re-addressed to the player who cannot be used.
@ 2022-04-16 3:41 AM (#30536 - in reply to #30522) (#30536) Top

CJK



Posts: 10

Country : Germany

CJK posted @ 2022-04-16 3:41 AM

For Record Score, does the goal shot also count as part of the path? Especially, if one team has a player next to the opposite goalkeeper, can the same order of players count twice (since this player can kick the ball directly or diagonally into the goal) or is this counted as the same path?
@ 2022-04-16 10:24 AM (#30537 - in reply to #30522) (#30537) Top

kiwijam



Posts: 178
100202020
Country : New Zealand

kiwijam posted @ 2022-04-16 10:24 AM

I have some clarifications for the optimizers. Please correct me if I'm wrong.

10. Opti-Road:
There is an error with the example. The column digits should be 22212, not 21212.
Also there is an error with the example answer key: the score for the example is 8, not 9.

11. From 0 to 9:
Without parentheses, we will always do multiplication and division (x and /) before addition and subtraction (_PLUS_ and -). Also, dividing by 0 is not allowed.

12. Record Score:
Total score is number of white paths plus number of black paths. The example is simple so I attach another one.
In this, White has 1 path, 1235674 (this is from the previous question from Christian - I think it is not important which direction #4 scores?).
And Black has 2x2=4 paths, 1234567, 1234576, 1324567, 1324576. It is not possible to go from #4 to #6 directly.
And so the total score for this example is 5.




(Record Score Example.png)



Attachments
----------------
Attachments Record Score Example.png (84KB - 2 downloads)
@ 2022-04-16 12:05 PM (#30538 - in reply to #30529) (#30538) Top

moeve



Posts: 2

Country : Germany

moeve posted @ 2022-04-16 12:05 PM

What about CJK's question:
CJK - 2022-04-14 10:07 PM
Is it allowed to use programs or similar things, especially for the optimization puzzles?

Of course, programming is usually not allowed in puzzle contests -- but ususally there are no optimization puzzles and especially for No. 11 it is obviously quite tempting to do some... ;)
@ 2022-04-16 1:25 PM (#30539 - in reply to #30536) (#30539) Top

Riad Khanmagomedov



Posts: 187
10020202020
Country : Russia

Riad Khanmagomedov posted @ 2022-04-16 1:25 PM

CJK - 2022-04-16 3:41 AM

For Record Score, does the goal shot also count as part of the path? Especially, if one team has a player next to the opposite goalkeeper, can the same order of players count twice (since this player can kick the ball directly or diagonally into the goal) or is this counted as the same path?

This counts as the same path.
@ 2022-04-16 1:39 PM (#30540 - in reply to #30537) (#30540) Top

Riad Khanmagomedov



Posts: 187
10020202020
Country : Russia

Riad Khanmagomedov posted @ 2022-04-16 1:39 PM

kiwijam - 2022-04-16 10:24 AM

I have some clarifications for the optimizers. Please correct me if I'm wrong.

10. Opti-Road:
There is an error with the example. The column digits should be 22212, not 21212.
Also there is an error with the example answer key: the score for the example is 8, not 9.

11. From 0 to 9:
Without parentheses, we will always do multiplication and division (x and /) before addition and subtraction (_PLUS_ and -). Also, dividing by 0 is not allowed.

12. Record Score:
Total score is number of white paths plus number of black paths. The example is simple so I attach another one.
In this, White has 1 path, 1235674 (this is from the previous question from Christian - I think it is not important which direction #4 scores?).
And Black has 2x2=4 paths, 1234567, 1234576, 1324567, 1324576. It is not possible to go from #4 to #6 directly.
And so the total score for this example is 5.

Thanks James:
10. You're right, I'll correct the example and the meaning of the expression in the answer format.
11. Yes.
12. Yes.
@ 2022-04-16 9:50 PM (#30541 - in reply to #30522) (#30541) Top

Christian



Posts: 4

Country : France

Christian posted @ 2022-04-16 9:50 PM

Hello,

For optimizer 11, is 2_PLUS_3=5 an equality, or must there be an arithmetic sign on both sides of the equality sign = ?
@ 2022-04-16 10:26 PM (#30542 - in reply to #30540) (#30542) Top

prasanna16391



Posts: 1604
1000500100
Country : India

prasanna16391 posted @ 2022-04-16 10:26 PM

I've uploaded a new PB with these changes.
@ 2022-04-17 12:20 AM (#30544 - in reply to #30541) (#30544) Top

Riad Khanmagomedov



Posts: 187
10020202020
Country : Russia

Riad Khanmagomedov posted @ 2022-04-17 12:20 AM

Christian - 2022-04-16 9:50 PM

Hello,

For optimizer 11, is 2_PLUS_3=5 an equality, or must there be an arithmetic sign on both sides of the equality sign = ?

Hello Christian,
2_PLUS_3=5 is accepted as an answer.
@ 2022-04-17 3:32 PM (#30545 - in reply to #30522) (#30545) Top

forcolin




Posts: 170
100202020
Country : ITALY

forcolin posted @ 2022-04-17 3:32 PM

For Mechanical Sudoku: Can any of the fragments overlap with one of the existing givens?
For LMI road: can two shaded cells (or half cells (share a side?
stefano
@ 2022-04-17 6:30 PM (#30546 - in reply to #30545) (#30546) Top

Riad Khanmagomedov



Posts: 187
10020202020
Country : Russia

Riad Khanmagomedov posted @ 2022-04-17 6:30 PM

forcolin - 2022-04-17 3:32 PM

For Mechanical Sudoku: Can any of the fragments overlap with one of the existing givens?
For LMI road: can two shaded cells (or half cells (share a side?
stefano

Hi Stefano,
1. It is not forbidden, but the fragments do not overlap each other.
2. Yes.
@ 2022-04-19 12:02 AM (#30547 - in reply to #30545) (#30547) Top

Barbitos



Posts: 1

Country : FRANCE

Barbitos posted @ 2022-04-19 12:02 AM

Hi, what about -2*-4=8? it would give more points but i guess it could also be forbidden since in that case the "-" sign is not really used as an operator
@ 2022-04-19 11:55 AM (#30549 - in reply to #30529) (#30549) Top

Carlos



Posts: 5

Country : France

Carlos posted @ 2022-04-19 11:55 AM

Hello,
If I am not mistaken, CJK's question doesn't have an answer yet. It would be convenient to know if we have to work only with paper/pencil for the optimization problems or not, in order to be rated with the same criteria.
Thank you very much!
@ 2022-04-19 3:57 PM (#30551 - in reply to #30538) (#30551) Top

moeve



Posts: 2

Country : Germany

moeve posted @ 2022-04-19 3:57 PM

moeve - 2022-04-16 9:05 AM
What about CJK's question:
CJK - 2022-04-14 10:07 PM
Is it allowed to use programs or similar things, especially for the optimization puzzles?

Of course, programming is usually not allowed in puzzle contests -- but ususally there are no optimization puzzles and especially for No. 11 it is obviously quite tempting to do some... ;)

?
@ 2022-04-19 5:43 PM (#30552 - in reply to #30522) (#30552) Top

forcolin




Posts: 170
100202020
Country : ITALY

forcolin posted @ 2022-04-19 5:43 PM

puzzle 11: only integer numbers or decimal allowed?
@ 2022-04-19 10:20 PM (#30553 - in reply to #30552) (#30553) Top

Riad Khanmagomedov



Posts: 187
10020202020
Country : Russia

Riad Khanmagomedov posted @ 2022-04-19 10:20 PM

forcolin - 2022-04-19 5:43 PM

puzzle 11: only integer numbers or decimal allowed?

The intermediate result can be fractional, but it is forbidden to construct numbers using a dot or comma.
@ 2022-04-20 12:45 PM (#30554 - in reply to #30551) (#30554) Top

MastrclaySeine



Posts: 1

Country : The Netherlands

MastrclaySeine posted @ 2022-04-20 12:45 PM

moeve - 2022-04-19 3:57 PM

moeve - 2022-04-16 9:05 AM
What about CJK's question:
CJK - 2022-04-14 10:07 PM
Is it allowed to use programs or similar things, especially for the optimization puzzles?

Of course, programming is usually not allowed in puzzle contests -- but ususally there are no optimization puzzles and especially for No. 11 it is obviously quite tempting to do some... ;)

?


Another request then to get an answer to this question. Not sure why this question has been ignored three times?
@ 2022-04-20 3:50 PM (#30555 - in reply to #30522) (#30555) Top

Carlos



Posts: 5

Country : France

Carlos posted @ 2022-04-20 3:50 PM

Hello,
It would be convenient to know if we have to use only paper/pencil for optimization problems, in order to be rated on the same criteria...
@ 2022-04-20 4:36 PM (#30556 - in reply to #30546) (#30556) Top

Nizz



Posts: 9

Country : Denmark

Nizz posted @ 2022-04-20 4:36 PM

Riad Khanmagomedov - 2022-04-17 2:30 PM

forcolin - 2022-04-17 3:32 PM

For Mechanical Sudoku: Can any of the fragments overlap with one of the existing givens?

Hi Stefano,
1. It is not forbidden, but the fragments do not overlap each other.


OK. Back to square one on that one.
@ 2022-04-20 11:18 PM (#30557 - in reply to #30522) (#30557) Top

Carlos



Posts: 5

Country : France

Carlos posted @ 2022-04-20 11:18 PM

Hello,
It would be convenient to know if we have to use only paper/pencil for the optimization problems, in order to be rated on the same criteria...

Edited by Carlos 2022-04-20 11:43 PM
@ 2022-04-21 12:20 AM (#30558 - in reply to #30557) (#30558) Top

Riad Khanmagomedov



Posts: 187
10020202020
Country : Russia

Riad Khanmagomedov posted @ 2022-04-21 12:20 AM

Carlos - 2022-04-20 11:18 PM

Hello,
It would be convenient to know if we have to use only paper/pencil for the optimization problems, in order to be rated on the same criteria...

Hello,
I always use only paper and pencil, because I am not a programmer.
@ 2022-04-21 12:28 AM (#30559 - in reply to #30522) (#30559) Top

Riad Khanmagomedov



Posts: 187
10020202020
Country : Russia

Riad Khanmagomedov posted @ 2022-04-21 12:28 AM

I see errors in some answers to 12. Record score. Two white players cannot pass to each other if there is a black player on the line between them. And two black players cannot be connected by a straight line if there is a white player between them.
@ 2022-04-21 12:50 PM (#30560 - in reply to #30558) (#30560) Top

CJK



Posts: 10

Country : Germany

CJK posted @ 2022-04-21 12:50 PM

Riad Khanmagomedov - 2022-04-20 7:20 PM
Hello,
I always use only paper and pencil, because I am not a programmer.

Hello Riad,
I have to admit that it is a little bit frustrating that this simple question cannot be clearly answered by you, even after being repeated five times. I do not really understand why it is that difficult to just say "yes, programming is allowed" or "no, programming is not allowed".
To be clear: I have no clear opinion about whether it should be allowed or not (I haven't programmed yet and I probably won't have time for it anymore), but I dislike the fact that you ignore one specific question for a whole week while answering every other question just a few hours later. For this contest it may be too late, but please don't do this in future contests again.
@ 2022-04-21 7:10 PM (#30561 - in reply to #30522) (#30561) Top

jo97



Posts: 1

Country : France

jo97 posted @ 2022-04-21 7:10 PM

Hello%2C%0D%0AFor+the+optimizer+equation%2C+exponent+and+negation+are+allow+or+not%3F+Because+technically+exponent+can+be+write+without+using+additionnal+arithmetic+sign%3A%0D%0A9%3D3%C2%B2+et+9+%3D+3%5E2%3F
@ 2022-04-21 7:36 PM (#30562 - in reply to #30560) (#30562) Top

Riad Khanmagomedov



Posts: 187
10020202020
Country : Russia

Riad Khanmagomedov posted @ 2022-04-21 7:36 PM

CJK - 2022-04-21 12:50 PM

Riad Khanmagomedov - 2022-04-20 7:20 PM
Hello,
I always use only paper and pencil, because I am not a programmer.

Hello Riad,
I have to admit that it is a little bit frustrating that this simple question cannot be clearly answered by you, even after being repeated five times. I do not really understand why it is that difficult to just say "yes, programming is allowed" or "no, programming is not allowed".
To be clear: I have no clear opinion about whether it should be allowed or not (I haven't programmed yet and I probably won't have time for it anymore), but I dislike the fact that you ignore one specific question for a whole week while answering every other question just a few hours later. For this contest it may be too late, but please don't do this in future contests again.

Hello Christian,
If I knew the answers to all the questions, of course I would have suggested it. I don't program and participate in all tournaments without resorting to this process. Let's leave this question to the discretion of each puzzler.
@ 2022-04-21 8:15 PM (#30563 - in reply to #30522) (#30563) Top

Swagatam



Posts: 45
2020
Country : India

Swagatam posted @ 2022-04-21 8:15 PM

A couple of questions: For optimizer puzzles, any optimizer puzzle

1. How do you approach to final solution from your initial guess/solution?
2. How do you become aware of that you have reached to the optimum solution?
@ 2022-04-21 8:55 PM (#30564 - in reply to #30561) (#30564) Top

Riad Khanmagomedov



Posts: 187
10020202020
Country : Russia

Riad Khanmagomedov posted @ 2022-04-21 8:55 PM

Please do not use the exponent operator in 11. From 0 to 9.
@ 2022-04-21 8:58 PM (#30565 - in reply to #30561) (#30565) Top

Riad Khanmagomedov



Posts: 187
10020202020
Country : Russia

Riad Khanmagomedov posted @ 2022-04-21 8:58 PM

%5BQUOTE%5Djo97+%2D+2022%2D04%2D21++7%3A10+PM%0D%0A%0D%0AHello%2C%0D%0AFor+the+optimizer+equation%2C+exponent+and+negation+are+allow+or+not%3F+Because+technically+exponent+can+be+write+without+using+additionnal+arithmetic+sign%3A%0D%0A9%3D3%C2%B2+et+9+%3D+3%5E2%3F%5B%2FQUOTE%5D%0D%0AHello%2C%0D%0ANot+allowed%2E
@ 2022-04-21 10:47 PM (#30566 - in reply to #30563) (#30566) Top

auroux



Posts: 126
10020
Country : France

auroux posted @ 2022-04-21 10:47 PM

Swagatam - 2022-04-21 7:15 AMA couple of questions: For optimizer puzzles, any optimizer puzzle1. How do you approach to final solution from your initial guess/solution?2. How do you become aware of that you have reached to the optimum solution?
That depends on the specific optimizer, but basically I first try to build a solution, any solution. Then to think about how happy I am with that solution in the context of the quantity to be optimized, whether my solution could be improved by small changes, or whether a redesign from scratch, building the solution a different way, would likely give a much better answer. After a few attempts, usually, one has a sense of whether one has produced something good (possibly close to optimal) or if it feels that there are some guiding principles that aren't understood yet. And of course, often, there are BIG surprises when discovering what other people have managed to do with the same optimizer problem. I don't want to comment too much while the contest is going on, plus I'd risk making a fool of myself if I made hasty pronouncements and it turns out my solutions are really really far from the optimal ones, but after initial skepticism I became quite fond of this year's optimizers. I think they are extremely well designed, in the sense that one can profitably approach them by hand and get a sense of how they work; and, if I dare say so, I don't think computer brute force search would be particularly more helpful on these than careful thinking and formulating intuition.
@ 2022-04-21 10:52 PM (#30567 - in reply to #30559) (#30567) Top

auroux



Posts: 126
10020
Country : France

auroux posted @ 2022-04-21 10:52 PM

Riad Khanmagomedov - 2022-04-20 11:28 AMI see errors in some answers to 12. Record score. Two white players cannot pass to each other if there is a black player on the line between them. And two black players cannot be connected by a straight line if there is a white player between them.
I hope I am not one of those with errors. I have a solution that works well on paper, and proofread what I input into the submission box, but still am not confident that I encoded my solution correctly. Forming the answer key was the least enjoyable aspect of working on this optimizer, perhaps because I feel really bad at encoding/decoding grid coordinates when letters are used in both directions. (The problem itself was very interesting.)

Edited by auroux 2022-04-21 10:55 PM
@ 2022-04-22 10:49 AM (#30574 - in reply to #30522) (#30574) Top

kiwijam



Posts: 178
100202020
Country : New Zealand

kiwijam posted @ 2022-04-22 10:49 AM

I was seeing strange messages earlier like "contest is over" and "click link to participate unofficially", even though there is still 13 hours left.
But when I returned to the answer page after submitting it looked normal, so I think they can be ignored...
@ 2022-04-22 10:57 AM (#30575 - in reply to #30574) (#30575) Top

Administrator



20001000100100100100
Country : India

Administrator posted @ 2022-04-22 10:57 AM

kiwijam - 2022-04-22 10:49 AM

I was seeing strange messages earlier like "contest is over" and "click link to participate unofficially", even though there is still 13 hours left.
But when I returned to the answer page after submitting it looked normal, so I think they can be ignored...
The contest end time was set incorrectly, hence the confusing error message. It was sorted few hours back.
If anyone else is seeing message like "contest is over", request to refresh the submission page.
@ 2022-04-22 2:35 PM (#30577 - in reply to #30566) (#30577) Top

Swagatam



Posts: 45
2020
Country : India

Swagatam posted @ 2022-04-22 2:35 PM

auroux - 2022-04-21 10:47 PM

Swagatam - 2022-04-21 7:15 AMA couple of questions: For optimizer puzzles, any optimizer puzzle1. How do you approach to final solution from your initial guess/solution?2. How do you become aware of that you have reached to the optimum solution?
That depends on the specific optimizer, but basically I first try to build a solution, any solution. Then to think about how happy I am with that solution in the context of the quantity to be optimized, whether my solution could be improved by small changes, or whether a redesign from scratch, building the solution a different way, would likely give a much better answer. After a few attempts, usually, one has a sense of whether one has produced something good (possibly close to optimal) or if it feels that there are some guiding principles that aren't understood yet. And of course, often, there are BIG surprises when discovering what other people have managed to do with the same optimizer problem. I don't want to comment too much while the contest is going on, plus I'd risk making a fool of myself if I made hasty pronouncements and it turns out my solutions are really really far from the optimal ones, but after initial skepticism I became quite fond of this year's optimizers. I think they are extremely well designed, in the sense that one can profitably approach them by hand and get a sense of how they work; and, if I dare say so, I don't think computer brute force search would be particularly more helpful on these than careful thinking and formulating intuition.

Thank you @auroux for the comment. Actually this is how I solve these problems: firstly, finding an initial solution/taking a guess, then improving the solution till I'm satisfied. But, this time I thought maybe by any chance there is another way of doing this; like in other puzzles, they have very good and well designed pathway to reach to the one and only solution and if you follow the logical pathway you know that every step you take you are correct and will reach to the only solution. For optimizer puzzles, in the same way I can reach to a solution but most of the times I can't be sure whether it is optimal. I can only know that after checking top solutions once the contest is over. Again, thank you for your opinion, this clears my dilemma.
@ 2022-04-22 3:04 PM (#30578 - in reply to #30537) (#30578) Top

Swagatam



Posts: 45
2020
Country : India

Swagatam posted @ 2022-04-22 3:04 PM

About the Record Score Example posted by Kiwijam, is that a valid solution? Because, the instruction says that own goal is not allowed. Here, BLACK numbered 6 player is on the row (row R) from where he can shoot the ball to his own goal. Similarly for WHITE numbered 3 player, he can shoot the ball diagonally to his own goal. Or, is it just calculation of own goal is not allowed?
@ 2022-04-22 3:32 PM (#30579 - in reply to #30522) (#30579) Top

kiwijam



Posts: 178
100202020
Country : New Zealand

kiwijam posted @ 2022-04-22 3:32 PM

Hi Swagatam, Riad's example has players at those same locations too. They are allowed to stand where they can see their own goal. But when you count the number of goal paths, you can only include paths that end at the opposite goal from the start goalkeeper #1.
@ 2022-04-22 3:39 PM (#30580 - in reply to #30579) (#30580) Top

Swagatam



Posts: 45
2020
Country : India

Swagatam posted @ 2022-04-22 3:39 PM

kiwijam - 2022-04-22 3:32 PM

Hi Swagatam, Riad's example has players at those same locations too. They are allowed to stand where they can see their own goal. But when you count the number of goal paths, you can only include paths that end at the opposite goal from the start goalkeeper #1.

Oh, I see now. Thank you.
@ 2022-04-22 4:05 PM (#30581 - in reply to #30522) (#30581) Top

Carlos



Posts: 5

Country : France

Carlos posted @ 2022-04-22 4:05 PM

Hello,
I need clarifications about the second optimizer puzzle:
- Is it allowed for a side of an equality to begin with a _PLUS_ or - sign? Such as 8_PLUS_3 = _PLUS_11 or 5 - 6 = -1?
- Can two arithmetic signs be consecutive, like in 8x-3 = 6x-4? Here, the cross symbol 'x' and the minus sign '-' are next to each other. Is it a valid equation?
@ 2022-04-22 6:50 PM (#30582 - in reply to #30522) (#30582) Top

prasanna16391



Posts: 1604
1000500100
Country : India

prasanna16391 posted @ 2022-04-22 6:50 PM

From Riad: of these, only 5-6=-1 is valid.
@ 2022-04-22 7:53 PM (#30583 - in reply to #30522) (#30583) Top

Hugo



Posts: 4

Country : The Netherlands

Hugo posted @ 2022-04-22 7:53 PM

I want to submit all my answers, but I am also getting the message ""April contest 2022 is over. However, you can participate unofficially using this link."" I tried to refresh the page but I still can't submit. I don't see a submit button.
@ 2022-04-22 8:35 PM (#30584 - in reply to #30522) (#30584) Top

prasanna16391



Posts: 1604
1000500100
Country : India

prasanna16391 posted @ 2022-04-22 8:35 PM

Try again now. There's some bug so for now I just changed the end time. I'll fix it soon and we won't consider any submissions after the end time announced (4 hours from now) as official but you have till then to submit.
@ 2022-04-23 12:33 AM (#30585 - in reply to #30562) (#30585) Top

Nizz



Posts: 9

Country : Denmark

Nizz posted @ 2022-04-23 12:33 AM

Riad Khanmagomedov - 2022-04-21 3:36 PM

CJK - 2022-04-21 12:50 PM

I have to admit that it is a little bit frustrating that this simple question cannot be clearly answered by you, even after being repeated five times. I do not really understand why it is that difficult to just say "yes, programming is allowed" or "no, programming is not allowed".
To be clear: I have no clear opinion about whether it should be allowed or not (I haven't programmed yet and I probably won't have time for it anymore), but I dislike the fact that you ignore one specific question for a whole week while answering every other question just a few hours later. For this contest it may be too late, but please don't do this in future contests again.

Hello Christian,
If I knew the answers to all the questions, of course I would have suggested it. I don't program and participate in all tournaments without resorting to this process. Let's leave this question to the discretion of each puzzler.


1. The contest is literally called "Riad Khanmagomedov's April Contest". It is your contest. You decide the rules :-) If someone else decides the rules, and you just run the contest, you should know who to ask

2. For the contests with an instruction booklet, it seems there is a standard wording in the rules:

Outside solving help of any kind is not permitted. This includes but is not limited to:
assistance of any kind from any other person; prepared notes, books, calculators,
computers, or tools other than items explicitly permitted.

I would assume this goes for this contest as well, and for any other contest on the site with no explicit rules.
@ 2022-04-23 9:21 AM (#30586 - in reply to #30522) (#30586) Top

debmohanty




1000500100100100202020
Country : India

debmohanty posted @ 2022-04-23 9:21 AM

Optimizer Submissions

Submissions to Optimizer puzzles here.

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

@ 2022-04-23 11:08 AM (#30587 - in reply to #30522) (#30587) Top

Carlos



Posts: 5

Country : France

Carlos posted @ 2022-04-23 11:08 AM

Woah it's nice to see all the puzzlers' solutions for the optimizers!
About the equation, the first three are not valid: "_PLUS_65821=-9403x-7" and "65821=-9403x-7" use two consecutive operators, which is not allowed (based on an answer on this thread). Maybe you will cap these solutions to the optimal one (with score 658210), since this issue was not clarified in the Puzzle Booklet and was fixed only the last day of competition.
Huge thanks for all these beautiful puzzles, some classic ones were really hard and very enjoyable to solve!
@ 2022-04-23 2:24 PM (#30589 - in reply to #30587) (#30589) Top

Nizz



Posts: 9

Country : Denmark

Nizz posted @ 2022-04-23 2:24 PM

Carlos - 2022-04-23 7:08 AM

Woah it's nice to see all the puzzlers' solutions for the optimizers!
About the equation, the first three are not valid: "_PLUS_65821=-9403x-7" and "65821=-9403x-7" use two consecutive operators, which is not allowed (based on an answer on this thread). Maybe you will cap these solutions to the optimal one (with score 658210), since this issue was not clarified in the Puzzle Booklet and was fixed only the last day of competition.
Huge thanks for all these beautiful puzzles, some classic ones were really hard and very enjoyable to solve!

Yes, THANK YOU RIAD for some really great puzzles. I love the format, much more satisfying than 60/90 minute frenzy with the printer
On first seeing them, I thought I would hate the optimizations, but in the end I loved them all. It turns out the only thing I really hate is Mechanical Sudoku. The number equation was the least fun of the optimization - mostly because I resolved to manual brute force,. I am happy to see that I managed "local optimums" for Record Score (best solution with symmetrical paths), and Opti-Road (best solution with G=g (or V=v).
As for the top three solutions for "From 0 To 9":
Since these solvers were aware of the possibility to use negation/unary minus, which was explicitly endorsed by Riad on the forum, I would think it fair to allow them the top solution utilizing it:
-65821=-9403x7



Edited by Nizz 2022-04-23 2:24 PM
@ 2022-04-23 3:13 PM (#30590 - in reply to #30587) (#30590) Top

Riad Khanmagomedov



Posts: 187
10020202020
Country : Russia

Riad Khanmagomedov posted @ 2022-04-23 3:13 PM

Carlos - 2022-04-23 11:08 AM

Woah it's nice to see all the puzzlers' solutions for the optimizers!
About the equation, the first three are not valid: "_PLUS_65821=-9403x-7" and "65821=-9403x-7" use two consecutive operators, which is not allowed (based on an answer on this thread). Maybe you will cap these solutions to the optimal one (with score 658210), since this issue was not clarified in the Puzzle Booklet and was fixed only the last day of competition.
Huge thanks for all these beautiful puzzles, some classic ones were really hard and very enjoyable to solve!

Thanks Paul,
I have completed the check and you will see the preliminary results very soon.
@ 2022-04-23 3:20 PM (#30591 - in reply to #30589) (#30591) Top

Riad Khanmagomedov



Posts: 187
10020202020
Country : Russia

Riad Khanmagomedov posted @ 2022-04-23 3:20 PM

Nizz - 2022-04-23 2:24 PM


Yes, THANK YOU RIAD for some really great puzzles. I love the format, much more satisfying than 60/90 minute frenzy with the printer
On first seeing them, I thought I would hate the optimizations, but in the end I loved them all. It turns out the only thing I really hate is Mechanical Sudoku. The number equation was the least fun of the optimization - mostly because I resolved to manual brute force,. I am happy to see that I managed "local optimums" for Record Score (best solution with symmetrical paths), and Opti-Road (best solution with G=g (or V=v).
As for the top three solutions for "From 0 To 9":
Since these solvers were aware of the possibility to use negation/unary minus, which was explicitly endorsed by Riad on the forum, I would think it fair to allow them the top solution utilizing it:
-65821=-9403x7


Thank you Nis,
In your solution 12. Record Score there were forbidden passes, which reduced your result.

The result -65821 would be minimal, but it was necessary to strive for the maximum.
@ 2022-04-23 8:40 PM (#30593 - in reply to #30522) (#30593) Top

Christian



Posts: 4

Country : France

Christian posted @ 2022-04-23 8:40 PM

Hello,

Sorry, but it seems my answer for problem 12 is not counted.
Sincerely,
Christian
@ 2022-04-23 8:51 PM (#30594 - in reply to #30591) (#30594) Top

Nizz



Posts: 9

Country : Denmark

Nizz posted @ 2022-04-23 8:51 PM

Riad Khanmagomedov - 2022-04-23 11:20 AM

Nizz - 2022-04-23 2:24 PM



Thank you Nis,
In your solution 12. Record Score there were forbidden passes, which reduced your result.
The result -65821 would be minimal, but it was necessary to strive for the maximum.

Indeed, and indeed.
I also see that I had errors in 2 of the regular puzzles. Bummer.
It does seem like some scores are missing for puzzle 10 (including mine) - not sure if this is also due to invalidity of the answers? Seems unlikely, since "moeve" submitted what looks like the same solution as me, modulo reflection, and scored 8 points for it
Anyway: Thank you, once again.
@ 2022-04-23 9:54 PM (#30595 - in reply to #30593) (#30595) Top

Riad Khanmagomedov



Posts: 187
10020202020
Country : Russia

Riad Khanmagomedov posted @ 2022-04-23 9:54 PM

Christian - 2022-04-23 8:40 PM

Hello,

Sorry, but it seems my answer for problem 12 is not counted.
Sincerely,
Christian

Hello Christian,
It is noted on my sheet that you have 5 points. Sorry, we'll add it now.
@ 2022-04-23 10:10 PM (#30596 - in reply to #30594) (#30596) Top

Riad Khanmagomedov



Posts: 187
10020202020
Country : Russia

Riad Khanmagomedov posted @ 2022-04-23 10:10 PM

Nizz - 2022-04-23 8:51 PM

Riad Khanmagomedov - 2022-04-23 11:20 AM

Nizz - 2022-04-23 2:24 PM



Thank you Nis,
In your solution 12. Record Score there were forbidden passes, which reduced your result.
The result -65821 would be minimal, but it was necessary to strive for the maximum.

Indeed, and indeed.
I also see that I had errors in 2 of the regular puzzles. Bummer.
It does seem like some scores are missing for puzzle 10 (including mine) - not sure if this is also due to invalidity of the answers? Seems unlikely, since "moeve" submitted what looks like the same solution as me, modulo reflection, and scored 8 points for it
Anyway: Thank you, once again.

I checked the table with my sheet. Some points were not saved. I'll ask Deb to add them.
P10:
Jo97 11 points,
Nizz 8,
Ausmunchkin 5,
Tiralmo 2 (Tiralmo confused the setting digits horizontally and vertically, but I counted him 2 points).
P11:
Sugitakukun 11,
Christian 5.

Thanks!
@ 2022-04-23 10:13 PM (#30597 - in reply to #30522) (#30597) Top

Riad Khanmagomedov



Posts: 187
10020202020
Country : Russia

Riad Khanmagomedov posted @ 2022-04-23 10:13 PM

P10:
Jo 97 14 points!
@ 2022-04-23 10:21 PM (#30598 - in reply to #30522) (#30598) Top

Riad Khanmagomedov



Posts: 187
10020202020
Country : Russia

Riad Khanmagomedov posted @ 2022-04-23 10:21 PM

P10:
Jo97 14 points,
Nizz 8,
Ausmunchkin 5,
Tiralmo 2.
P12 (of course):
Sugitakukun 11,
Christian 5.
@ 2022-04-23 11:00 PM (#30599 - in reply to #30522) (#30599) Top

Riad Khanmagomedov



Posts: 187
10020202020
Country : Russia

Riad Khanmagomedov posted @ 2022-04-23 11:00 PM

Congratulations to James, Ken and Denis!
Thanks to all participants!
@ 2022-04-25 10:30 AM (#30603 - in reply to #30522) (#30603) Top

kiwijam



Posts: 178
100202020
Country : New Zealand

kiwijam posted @ 2022-04-25 10:30 AM

Thank you Riad, that was a great contest!
All the optimizers were interesting, and I think that the LMI-Road puzzle has a good new logic idea.
@ 2022-05-26 12:14 PM (#30656 - in reply to #30522) (#30656) Top

forcolin




Posts: 170
100202020
Country : ITALY

forcolin posted @ 2022-05-26 12:14 PM



a bit late, but Thanks Riad

Edited by forcolin 2022-05-26 12:16 PM