Puzzle Description Suppressed:Click below to view spoilers

#1: Kristen Vognild (kristen) on Apr 23, 2013

Nice little puzzle. I didn't have to guess.

Yes, nice puzzle. I got mixed up in the blue, but got it fixed.

after initial ll/cl you should only have the blue left to solve:

look at the two blue pixels in r4c3-4 and the two blue pixels in r4c6-7
each of them is part of a 2-clue or a 3-clue in each of those four columns
the ones in c3-4 cant both go into r3 or both go into r5 so at least one of them must be in r3c3 or r3c4, accounting for the first 1-clue in r3
do the same thing in c6-7 to show that the other 1-clue in r3 must go in either c6 or c7, so you can dot the rest of r3 except for those 4 columns
ll
now do similar logic on r9c3-4 and r9c6-7 to show that the two 1-clues in r10 must be either c3-4 and in either c6-7, dotting the rest of r9, which is only c1-2
ll to finish
no guessing
great solve on the blue

The black-first solve was nice.

In the blue,

Two-way logic on the 1 in r12:
- if it is in c5 then r11c5 is white
- if it is in c2, then r11c2 is white, forcing the two blue 1s in r11 into c4&6 making c5 white
So r11c5 is white.

Then I had to resort to some out-of-the-box logic.

Notice the four 1s in r5. Each one of those 1s are restricted to a two-pixel spot where they can fit. For instance the first 1 can only fit in c1 or c2, and the second 1 can only fit into c3 or c4.

Now notice the vertical clues that cross it in c3 and 4. They are both greater than 1. Since only one pixel in r5 can be blue in c3 and 4, that means that one of the pixels above in r3 must be blue in c3 or 4.

So keep in mind that one pixel in r3c3-4 must be blue.

Now the same arguments apply to c6-7.
-> One (and only one) pixel of r5c6-7 must be blue.
-> Both c6 & 7 have clues larger than 1
-> One of those clues must go down into r5 while one goes up into r3.
-> Therefore one of the pixels in r3c6-7 must be blue.

Now we know that r3's clues are fulfilled within c3-4 and c6-7. That means r3 c1,2,8,&9 can be dotted.

Then LL to finish

Hey bug, it looks like we looked at the same thing two slightly different ways and almost at the same time. You type faster than I do. It must be the lack of capitals. ;)

plus i wrote a lot less than you did
haha

Now I tried to solve my own puzzle.
Yes, it can be solved with pure line logic (thanks to Gods) :)

Thomas, while it can be solved with pure logic, it cannot be solved with only line logic. Line logic looks at *only one line at a time*.

All of the black, red, and green can be placed with line logic. It runs out however when the two blue 9 clues and one more blue pixel (c9r8) have been placed. At that point, you will need to look at more than one row or column at a time in order to place another pixel. There are still logical moves, but not Line Logic.

Nice solve & idea Thomas. Maybe you might want to see one of mine from the past #12936

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While logic *is* logic, it's a bit like saying a cow is a cow. If I bought a beef cow and the farmer delivered me a milk cow (which is all bones and udder) I would be very upset. Even though milk caws are fine if you want milk, they're not what I was sold. Line logic is a specific kind of logic used in these puzzles. Some sites restrict makers to only line-logic puzzles. Here any kind is allowed - and even puzzles that cannot be solved logically.

This is obviously less calamitous than the cow example, but if someone says that a puzzle is "line logic" solvable then it should not need any advanced techniques. Otherwise, just say that it is "logically solvable".

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Found to be solvable with moderate lookahead by gator.

Show: Spoilers

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