Sudoku

[mossy nebula]

Discuss sudoku here! Solving and setting discussions are both welcome, as are any variants - or even just classic puzzles!

[pliant drift]

Hi

[mossy nebula]

@rancid saffron did you have a chance to give that puzzle a go in the end?

[rancid saffron]

I may do it today after i finish my homework! I'll let you know how it goes

Its a bit intimidating tbh lol

[mossy nebula]

Would you like me to make a classic 4x4 so you can get an idea of the regular sudoku rules before you try this one? It should be doable either way but if you do a classic 4x4 first you might have some idea of the flow of a puzzle I guess

[rancid saffron]

Oh yeah that'd be good

[mossy nebula]

Alright here you go. Should be a fairly quick solve hopefully! https://tinyurl.com/yv43t9xl

[rancid saffron]

Ooh okay i'll give it a try when i get the time! Im at school rn so i'll have to wait a while

[mossy nebula]

https://tinyurl.com/yrn9bm3s and here's the link to the more complicated puzzle from yesterday so you don't have to go searching for it later

[mossy nebula]

Sure, no worries! Let me know when you do get the chance!

[rancid saffron]

Solved it in 2 minutes! That was kinda fun

[mossy nebula]

Well done and congrats on your first sudoku!

[rancid saffron]

I wanna see if i can do the other one

[rancid saffron]

Ty!

[rancid saffron]

Lets see if i can crack this one now...

[mossy nebula]

Go for it! It's definitely trickier but if you look at each rule and think about what they mean for the numbers it's fairly approachable

[fossil plover]

Anyone have like actual sudoku?

[mossy nebula]

What do you mean actual sudoku?

Sudoku comes in many forms and all of it is sudoku

[fossil plover]

I meant like standard sudoku

Like the 9x9 one

[mossy nebula]

Personally I haven't made any 9x9s

But I have set 2 6x6s

And 4 or so 4x4s

[fossil plover]

Ooo

[mossy nebula]

But I don't think I can share most of the other 4x4s yet as they are going to be part of a ongoing puzzle series called "snackdoku" that publishes daily "snack" puzzles that are designed to be solvable in 2-5 minutes

I'll go find my 6x6s though - one second...

Oh I can share this one though @fossil plover

Arrometers

Normal 4x4 sudoku rules apply.

Normal fog of war rules apply - once a correct digit is placed in the grid, fog will be cleared in that cell and all surrounding cells (orthogonally and diagonally).

The sum of the digits on an arrow is equal to the value in the corresponding circle.

In addition, arrows are slow thermos with the bulb at the head and the tip at the circle.

On slow thermos, digits may not decrease moving along the thermo from bulb to tip.

CTC: https://tinyurl.com/ywcvesyb

[fossil plover]

This reminds me of like the 30+ minesweeper variants

[mossy nebula]

I guess it's mildly similar

[rancid saffron]

So its been like 15 minutes im getting my ass kicked lol
Its been kinda fun tho ngl

[mossy nebula]

Here's one of the 6x6s
Thermon't

CTC - https://tinyurl.com/yp5tlukp

• Normal 6x6 sudoku rules apply.
• The digits in each box form a orthogonally connected chain of consecutive numbers from 1 to 6.
• Black Kropki dots indicate a 1:2 ratio between digits. Not all dots are necessarily given.

[mossy nebula]

Do you want to share how far you've got and I can give you a hint maybe?

[rancid saffron]

Its okay i'll admit im kinda just putting in numbers to see what works

I'll solve it eventually

[mossy nebula]

(And here's my other 6x6)

Kropkisn't

Normal 6x6 sudoku rules apply.

All cells in the grid are connected orthogonally into one network by invisible lines.

Wherever a line in this network connects two orthogonally adjacent digits, the two digits must be either consecutive (White Kropki dot) or have a 1:2 ratio (Black Kropki dot).

Digits along thermometers increase from bulb to tip.

In addition, the path taken by each thermometer is necessarily part of the network of orthogonally connected cells.

The digit in the grey circle is odd.

CTC: https://tinyurl.com/ytor9hz5

[mossy nebula]

So that's probably not the best approach yeah. In terms of solving it logically I'd give 3 hints:

1. ||Look at the start and end of each thermo. What digits cannot go in each space?||
2. ||Look at the palindrome lines. Which digits have to be identical? Given this and the digits that are possible on each thermo space, how can you narrow down the possibilities further?||
3. ||Once you've narrowed down the possibilities fully, what does the thermo rule tell you about the order of the digits on each one?||

[fossil plover]

Don't understand the rules here

Nvm I figured out what it meant by palindrome lines and it took like less than 10 seconds to fix

[mossy nebula]

So the thermos are the thicker lines with a big circle at one end. The digits on each thermo increase from bulb to tip, meaning that the digit in the bulb is smaller than the one in the tip.

The palindrome lines read the same both ways. This means that in this case ||the first and last digits of each palindrome are the same||

[mossy nebula]

Ah ok

[fossil plover]

Trying to figure out what the line rule means

Like this is just the bulb to tip rule but I don't understand the line rule

[mossy nebula]

Yeah sorry that one's probably the hardest to understand out of my puzzles. Basically, there is a network of imaginary lines connecting all the cells in the grid in some way. Each neighbouring cell with a line between them are either consequtive (eg 3,4) or are in a 1:2 ratio (eg 6,3). The thermos have regular thermo rules applying to them but in addition, they are part of the network of lines (so you know that every neighbouring digit on a thermo has to either be consecutive or in a 1:2 ratio.)

I can give you a visual example if you still aren't sure

But to explain why the solution in the image you posted isn't right, the thermos in box 3 and box 6 don't follow the consequtive or 1:2 rule (ie 1,3 isn't valid and nor is 4,6 on a thermo)

(but of course usually they would be valid - it's just with this particular ruleset they aren't)

[mossy nebula]

Btw @fossil plover if you are struggling with that one I would recommend this one first - it is much easier

[fossil plover]

Oh no I'm just playing with my friends right now lol

[rancid saffron]

I DID IT

I had to pause it a few times so the timer says 35 minutes but it was over an hour lol

[mossy nebula]

Well done! Did you manage it with logic or guessing in the end? No worries if you did just guess but if so I'll show you the intended solution path.

[rancid saffron]

I honestly had a mix of both i brute force my way into many things lol

[mossy nebula]

Fair enough. I'll record the solution for you to take a look then

[rancid saffron]

Alrighty!

[fossil plover]

Got it btw

[mossy nebula]

Nice! Well done - that one is definitely a bit tricky to solve

[fossil plover]

The biggest problem was I just didn't understand the rule lol

[mossy nebula]

I hope this is ok - I don't edit/record videos very often

[fossil plover]

It became a lot easier once I understood

[mossy nebula]

Cool. Yeah sorry about it being a little hard to understand

[fossil plover]

you could have said that each adjacent number connected to the thermo is either a sequence or 1:2 ratio

(wait I'm just realizing it isn't just the thermos)

Wait if things are supposed to be a 1:2 ratio why does ||1,5 and 2,6 work||

[lofty wolf]

What about diagonal rules? (In a 9x9 grid, all the numbers in said x across the center also follow the rules of non repeats)

[mossy nebula]

Yes but the idea was the whole grid is connected in that way but some of the lines in the network are invisible - if it were just the thermos the solution wouldn't be unique for a couple of reasons - one of which is that you end up with this ambiguity

[fossil plover]

Oh wait is it just that there are very literally invisible lines?

[mossy nebula]

uh

hold on

[mossy nebula]

I might have missed a couple of lines because I did this quickly but this is what the network looks like once you draw it in

[fossil plover]

Well that would have been nice to know

[mossy nebula]

I mean it is in the rules - its just a matter of interpreting them. To adapt a phrase from Magic the Gathering - reading the rules explains the rules

[rancid saffron]

Ooooh so thats how i wa supposed to do it lol
Good to know

Turns out these things are kinda fun

[mossy nebula]

I'm glad you're enjoying them

[fossil plover]

Ah but I read it
And didn't understand :v

[mossy nebula]

A lot of people think sudoku is boring as all they see are computer-generated classic 9x9s which are often tedious and sometimes require guessing/bifurcating. When you get into human made puzzles though that use variant rules (or even just human made classics sometimes), they are often anything but boring! I think more people need to be introduced to human-made sudokus.

[mossy nebula]

Yeah that's honestly fair enough @fossil plover . As I said its not obvious when you first read it. Might I recommend this puzzle which uses a similar premise but is much easier? To explain this one, each box has to contain digits connected in order sort of like a snake.

(See the images for two possible correct boxes)