# Spiral Stumper Series: Tilepaint

Spiral Stumper Series is a $$5$$-puzzles series taken from the Final Round of a local (national) contest, KPK, which has been ended recently and authored by me. The theme is spiral and each puzzle is standalone (there will be no meta, etc.)

• The areas enclosed by bold lines are called "Tiles" and color the tiles with the following rules.
• The cells of a tile must all be colored with black or left uncolored.
• A number tells the number of black cells there has to be to the right or downward in the line/column.
• I dont get it. Solving a grid-puzzle implies that one has gone through the deduction needed. A detailed explanation by another user does not mean that he solved it faster than me. Why am I not awarded the check? – Omega Krypton Sep 27 at 3:06
• @OmegaKrypton I'm truly sorry for not rewarding the checkmark for you because my principle of giving a checkmark is purely based on this. i.e. In case there are multiple answers, I choose the one which explains the best the answer. Quoting from the link: "Imagine somebody finding your post months/years later and only reading your question and the accepted answer. Will it be a good experienced for the reader?" So sorry once again if that matters.. >< – athin Sep 27 at 3:17
• i don't actually mind, but then i could provide an answer with the deduction for every grid years later, and i get the check? doesnt this violate the "first-to-get-answer" principle? – Omega Krypton Sep 27 at 3:25
• If you provide the complete deduction before I'm giving the checkmark, I'll preferably give the checkmark for you as you're the first to answer. But, usually, as there's already an answer given a checkmark, it will be still there. It's because the given one is already answered completely and your edit won't add extra values compared to the accepted one. So for me, it's based on quality first, then if tied, based on speed. If there's only a single correct answer btw for some hours without any other answers, even if it's not completed, I'll still gladly accept it! – athin Sep 27 at 4:03

Some basic deductions (either "if this was shaded, there would be too many cells"; "if this was unshaded, there would be too few cells"; or "if this was shaded/unshaded, there would be no way to make up the remainder exactly with the remaining cells") get this far:

Next,

take a look at the center square. If that was unshaded, then all of the remaining regions in the 8 column would be shaded, and the 6 column on the left would have too many cells. So the center square is shaded.

Now look at the column

with the 4, on the far right. If it's satisfied with the size-4 region, then both the second and eighth rows have their column-3 regions shaded, making too many shaded cells in the third column.

So it must instead be satisfied with the top and bottom regions.

Finally,

consider the J-tetromino just right of the center. If it's shaded, then the rest of the 6 column is unshaded, and then we have too many unshaded cells in column 8. So the J-tetromino is unshaded, so the rest of column 6 is full...

...and basic deductions solve the rest of the puzzle.

• I'm still amazed with your solving AND writing up a detailed explanation in such a HIGH-speed... – athin Sep 25 at 8:46

Answer is here, hey, this is not too hard compared to your other ones :D

• This is served as the first puzzle to the finalists and I'd like to have them a nice and easy puzzle to start as a warm-up! Hope you still had some fun solving it, good job! :D – athin Sep 25 at 8:36