Connect 4 Draw
(Published on 30. January 2025, 04:32 by marty_sears)
- Mark and Simon have just finished a game of Connect 4. They are both too clever for each other, and so it resulted in a draw; the board became full of an equal number of red and yellow discs without either of them managing to get any horizontal, vertical or diagonal connected line of 4 discs of their colour. Recreate the end board state by colouring the holes red and yellow. The first two moves have been shown.
- Fill the discs with the digits 1-7 so that no digits repeat in any row or column.
- ARROWS: A digit on an arrow disc indicates the total number of discs seen in the indicated directions (combined) that match its own colour. (The arrow disc itself isn't included in the count.)
- RED DISCS: Two orthogonally adjacent red discs must be of different parity (one odd digit and one even digit.)
- YELLOW DISCS: Two orthogonally adjacent yellow discs must have a difference of at least 3.
Rules:
Please leave a comment if you enjoy :)
Solution code: Red discs in column 7, from top to bottom
Comments
on 8. February 2025, 21:19 by Klausku
I‘m not bad at connect 4, but that didn‘t help me solving this puzzle. After getting my head around the rule for two or more arrow on a disk, it flowed smoothly but slowly. I enjoyed it a lot. Thanks Marty.
on 7. February 2025, 14:18 by str
Beautiful. Thank you Marty!
on 6. February 2025, 11:27 by Lion Crow
That was the most fun game of Connect4 that I’ve ever played.
on 5. February 2025, 18:53 by Logerfo
Lovely puzzle, but something doesn't seem right. I got a deadly pattern, which I solved using the uniqueness argument. Solution validated on sudokupad, but invalid on logic masters, which probably means I got the coloring wrong. Can't spot the mistake, so maybe there's a degree of ambiguity?
Marty: I don't believe so, the puzzle has been tested and solved many times. What ambiguity are you getting? What solution code did you try?
Logerfo: "the board became full of an equal number of red and yellow discs" sorry, I missed this part of the ruleset... Cheers!
on 4. February 2025, 16:46 by Lorena
Very original and cleverly set, I enjoyed it a lot!
on 4. February 2025, 00:09 by NRB
Can someone clarify the arrow rules for me?
Marty: sure, what are you confused about? For example, a red 6 arrow disc would be pointing at a total of 6 red discs (not including itself)
on 3. February 2025, 23:32 by dzamie
This was a lot of fun, keeping the different rules in my head. Also the shortest solution code I've seen in some time, since it's less than 6 digits long!
on 3. February 2025, 16:46 by Clowns_rock
I really enjoyed this solve! One of my first puzzles above 1* and I got it in 35:52. The break in was so lovely and seeing it all come together was so nice :) nice to use colouring where it's basicly necessary instead of as extra help
on 2. February 2025, 18:17 by jakestilesowen
Great puzzle. It's incredible how much design space there is in sudoku and that excellent setters keep finding it to great effect.
on 2. February 2025, 13:53 by mscha
Wonderful! A typical Marty Sears: highly creative, new and unique combination of rules. Most time is spent figuring out how those rules interact and what the consequences are, which is my favourite type of puzzle.
Took me forever, but loved every minute of it.
on 31. January 2025, 17:54 by Paquet Voleur
Very fun! I agree that a joint solve by Mark and Simon would probably be highly entertaining. Thanks for the good moment Marty! (Who was playing which colour? I tried to see if I could recognize the type of strategy, but the most obvious, the thermos, was noticeably absent from your puzzle.)
on 31. January 2025, 12:48 by Franjo
Funny idea, presented in a beautiful construction (as expected…)! Thank you very much for creating and sharing another lovely piece of your work.
on 31. January 2025, 10:54 by goldennumber
Felt easier than 3* to me, great fun, nice idea
on 31. January 2025, 06:56 by waffles_the_dog
A fun puzzle, I didn't find the logic to be that difficult compared to my apparent inability to win at connect 4 :D
on 31. January 2025, 03:57 by Hamsterbase
What a wonderful puzzle. Really enjoyed it. Not sure it was as much as a 3 star, but I must confess I made a mistake at one point and had to backtrack. Many thanks to the setter.
on 31. January 2025, 03:16 by anormalperson
Great puzzle man, took a bit long because I forgot about the red and yellow discs rules but after I remembered about them it was smooth sailing from there
on 31. January 2025, 01:29 by madhupt
Can’t wait to see a constantly chuckling Simon live solve this brilliant puzzle! I hope both Mark and Simon solve this jointly taking turns to make one deduction each.
on 30. January 2025, 20:41 by sujoyku
Lovely puzzle! I did not know it was fun to play connect 4 on your own. But this puzzle has cleared all doubt. :)
Thank you, Marty!
on 30. January 2025, 19:59 by greyhathero
Didn't feel quite like 3*, but looking back I'm not sure I can call it easy. Just fun!
on 30. January 2025, 17:55 by GameWorksRP
Great idea with beautiful styling. Felt easier than a 3* puzzle but required the same time as one! This was for me an indication that I was truely focussed, which is always great! Amazing puzzle.
on 30. January 2025, 17:26 by gfoot
Nice idea, I like the creative styling of the grid! Most of the deductions were not too difficult to spot, so it has a nice natural flow to it.
on 30. January 2025, 15:15 by 9Rookienumbers
What a brilliant puzzle!
on 30. January 2025, 14:48 by Franktothejay
Almost immediately upon starting, was hoping the final deduction was going to be what it was... and of course it was. Loved this!
on 30. January 2025, 12:09 by Default
Nice puzzle! Maybe it's fun to actually play connect 4 like this. Draw numbers on your discs and never make a move that breaks a sudoku rule. It should be easy in the beginning, but near the end of the game you will get surprising strategies to beat your opponent. (Include the red/yellow disc restraints for advanced players)
on 30. January 2025, 08:02 by TheNineElements
Solve Time: 52:40
I rated this 3/5 difficulty.
Another great marty_sears puzzle!
Really enjoyed this puzzle, and it was a totally different experience than I expected. This is such a creative puzzle idea, and the connect 4 logic lead to a bunch of great deductions.
The break-in was the hardest part of this puzzle for me. I really struggled to wrap my head around the rules - but once I began understanding it better everything started coming together nicely. The break in felt 4* difficulty for me, but I'm not sure if this is due to the unfamiliar ruleset or if the logic was actually as tricky as I made it. I did originally forget that the arrow rule didn't include the base cell's own color as part of the count - so this definitely was self-inflicted confusion/complexity to some degree.
The midgame/endgame of the puzzle were more straightforward and very fun to work through. This part of the solve felt around 3* difficulty. All the connect-4 logic was wonderful and very enjoyable.
As such, I rated this puzzle 3/5 difficulty overall. I think it falls on the harder end of 3* puzzles, though. I really liked the idea of having the board be a valid connect-4 board when solved, having the same number of red & yellow cells due to the nature of game turns. This whole premise was brilliant & cleverly executed.
Thanks for sharing @marty_sears! I'm excited to see Simon or Mark's solves of the puzzle when one of them inevitably solve it on camera.
on 30. January 2025, 04:37 by ChinStrap
Wonderful. Even had the feeling of playing connect 4 for a lot of it. Really thematic feeling.
