Sudoku GP 2020

The results are out and will probably become official soon.

This weekend, the 7th round of Sudoku GP will be held. Some tips for solving the problems. 7. First seen odd/even. This is a cheap problem - probably about as easy as the example problem. If both numbers are given in all edges, then you need to start solving from the edges. Start with the numbers that appear only once and use the clues in the corners. If both clues have been used, then I recommend removing the clue - so that the clues that have not yet been used and that probably still need to be used are revealed. 8. Offset I recommend analyzing the gray squares more to see what options are there and what are not. Often, there is only one option in a gray square with the number following it. One thing to note is that, for example, if the 5th square of the 5th row is gray, then the 6th square of the 5th row cannot contain the numbers 4, 5 and 6, because otherwise the number in the gray square would end up in the same 3x3 box. The same principle applies to quite a few locations. 9. search 9 I recommend drawing circles around the 9s so that they become more noticeable. And write out on the arrows what variants they can have. You should also pay attention to the fact that the number 9 cannot be behind the arrow. This way you can exclude 9 from several places. The solution should generally start by finding the locations of the 9s. 10. Thermo is described in the 2nd round. 11. Numbered rooms If all the numbers are given in one row, then the locations of number 1 are quite easy to find. I recommend practicing this example problem and practicing yourself with what you can do in the problem. If a hint has been used, it should be crossed out so that the hints that are needed for further solving remain. Then they can be found more quickly. 12. Mathrax In general, this task is solved by marking out the even-even numbers and also writing out the variants in different boxes. This can be a rather difficult and unpleasant task. 13. Double sandwich Circle the locations of the numbers 1-5-9 - even if you don't know exactly which one goes there. The sum of the remaining numbers is 30. So if two numbers are given, it is possible to calculate the sum of the numbers that are outside the circles. For certain sums, there are not many variants. For example, if there are two numbers 12, then the only variant is 4 8, because 1, 5 and 9 cannot be included in the sum. 14. German whispers. The line alternates between large and small numbers, and the number 5 cannot be on the line. If there is a 4 of the small numbers on the line, then only 9s can be next to it. Similarly, only 1s can be next to 6. Only 8 and 9 next to 3. Only 1 and 2 next to 7. Only 7,8 and 9 next to 2. Only 1,2 and 3 next to 8. If you know which is large and which is small, then you can, for example, mark all the large numbers on the entire line.

The results of the 7th round are out. File attached. It's great that there are still those who consistently solve the puzzle, but towards the end, participation always starts to drop off a bit. Apparently the hot summers are the reason for this. I definitely encourage you to take part in the last round to improve your result.

The final round guide is also out.

Would it be necessary to write any instructions or ideas for the 8th round here in more detail? In general, all the variants are such that they should have been through the GP in some way and there should be nothing very complicated. It is definitely worth solving the so-called normal sudokus first and then starting to solve the liar sudokus - unless you are very confident in yourself. There are 2 possible approaches to solving liar sudokus. One option is the trial and error method. You assume that one is a liar and consider all the others correct. If it turns out that this is not the case, then you can be sure that this one must be correct. And then you continue solving with a similar method. The second and probably more effective option is to solve the sudokus at the beginning without looking at these additional rules. At some point, some kind of contradiction will probably arise somewhere, where it is possible to assume that the incorrect clue is, for example, emb-kumb. Then you can conclude that all the others are correct and then the matter will probably branch out. The situation is a little different with Liar Zones sudoku, where in each area there are 2 correct and 1 incorrect. You have to start noting which ones are definitely correct and which ones are incorrect (if they turn out to be correct). If you find 2, you can already deduce the third one. In general, I also noticed that liar sudokus give fewer points. I think this is a very nice gesture from the authors, because in principle all tasks are equally solvable and there are probably no very bad liar sudokus that can simply ruin the entire round.

The 8th round is over and although the official results for the last round are not yet out, there will probably be no changes in this regard. If anyone discovers in the near future that there will be minor changes in someone's place or something like that, you can let me know here or separately. Hopefully the table has been made correctly. In general, I got the numbers to match.

I will also summarize the summary results of this year's GP. 29 Estonians participated, which is quite a good result. 6 Estonians were present and sent their results in all rounds. 15 Estonians completed at least 6 rounds. 12 Estonians earned over 1000 points. In addition, three competitors were quite a bit short - probably due to a few typos this time. But next year is a new opportunity. I still encourage everyone to participate next year. This is a good opportunity to test your abilities and 40% of the sudokus are always classic sudokus, which should also be well suited to Vindi users. Since there will be no GP finals this year, the entire ranking is based on the preliminary rounds. So that's all for this year's sudoku GP. It is probably appropriate to wish you a happy end of the old year and see you in the new year.