A Lesson from the Professor

Normal sudoku rules apply. Clues outside the grid indicate the maximum sum of a group of connected ascending digits from that side in that row or column.

▶Our merchandise (including birthday merch) is here: ◀

▶ CTC FAN DISCORD SERVER◀


▶ OUR PATREON PAGE – JOIN THE COMMUNITY, SUPPORT US AND TRY OUR PUZZLE HUNTS◀

▶ OUR BACK CATALOGUE – ALL CATEGORISED WITH LINKS!◀

Miracle Sudoku is available on Android, Steam and App Store.

▶ THERMO SUDOKU is available too!◀

▶ TRY OUR CHESS SUDOKU APP◀

▶TRY OUR CLASSIC SUDOKU APP◀

▶TRY OUR SANDWICH SUDOKU APP◀

▶SEND US PUZZLES TO SOLVE/CONTACT US◀

▶FOLLOW US◀
Twitter: #crypticcracking
@crypticcracking

▶Music◀
Tim McCaskey plays Mozart's Sonata no 16 ("Sonata Facile")
▶SOFTWARE◀
Play the puzzle in the video by clicking the link under the video (above). Thanks to Sam Cappleman-Lynes and Sven Neumann for their work.
▶Logo Design◀
Melvyn Mainini

▶Opening Credits Design◀
Joel Blundell
▶ABOUT US◀
Hi! We're Simon Anthony and Mark Goodliffe, two of the UK's most enthusiastic puzzle solvers. We have both represented the UK at the World Sudoku Championships and the World Puzzle Championships. We're also "cryptic crossword" aficionados. Mark is the twelve-time winner of The Times championship and Simon is the former record holder for most consecutive correct solutions to The Listener crossword. We hope we can help your puzzle solving while also introducing you to some of the world's best puzzles.

Thank you for watching!
Simon and Mark

[richardstolk]

Hi Mark,
Nice to see that you found most of the logic relative quickly.
The top row was indeed the bottle neck, but you could have at least eliminated 1 from R1C3 sooner since the 17-clue could not be fullfilled anymore in that case.
Here is some more logic:
4 cannot be in R2C9 because of the 12-sum.
So 4 in R2 in block 2, which means that R1C5 cannot be 2; 2 in block 2 must be in R13C4; R7C4 = 8.
R3C5 is now either 5 or 6.
1 cannot be in R1C3; there is no way of building 17 in R1.
To complete the 36clue, the missing sum of 6 in C3 is either 1/5 or 2/4.
If it is 1/5; R1C3 = 2; R3C5 = 6 forcing R2C5 to be 3 and R1C5 to be 5. But now there are no possibilities building the 17-clue. So R23C3 must be 2/4.

But all in all it was a pleasure again to see you race through the largest part of the puzzle. I really admire your speed of calculating the possible combinations! :-)

[realtylerdb]

4:18 - I don't know why but that "What do you mean you knew it" made me so happy

[HienNguyenHMN]

maybe it's just me, but I like that Mark clears out the colours after the logic is "used up". It helps with future scanning (or rather, prevents mis-scanning).

[glum_hippo]

What a lovely puzzle idea from Richard! But kudos to the solver as well, Mark - you didn't miss a beat and saw right through this one like Superman with X-ray vision.

[BillLamoreaux]

"I love how this rule works, when I know what to do!" That's the story of my sudoku life. :-)

[michaelhill]

Brilliant puzzle, brilliant solver. Looking forward to the crossword solve.

[ericpraline]

The break-in is absolutely sublime. Got my knickers in a twist after that but got there in the end.

[Coyotek]

I thought the math-centric nature would make this fairly easy for me. I was wrong.

I spent about 20 minutes, broke, backtracked to find my error, got further, got *completely* stuck, ended up bifurcating (i.e., guessing), and while I did prove uniqueness to myself, I stumbled upon the final answer in a time of 1:05:31.

Tough puzzle!

[mceajc]

Oh my. I opened up the puzzle link and only then read the rules. I think I am going to sit this one out and watch Mark wrap his head around this one...

[randomcubing]

This is a marvellous yet devilish idea

[GeraSanz]

I jost loved this particular video! Hoe fast you found the logic for the 9-10. Amazing work Mark as always!

[smithtim]

rules were a bit unclear to me. I interpreted "maximum" to mean upper bound, as in the sum can't be greater than the clue, rather than it indicating that the clue HAD to be a sum in the row or column.

[thedavecwright]

Hmmm... got a bit scared off by the rule set, so decided to watch Mark solve it.

Having seen it, it looks like fun and approachable for someone at my standard... will keep an eye out for the next one!

[curtissumner]

41:40. Extremely daunting until you think about the general constraints that this unique rule applies. I feel like that's the case for a lot of these rulesets, is you need to think in more general terms than the individual cases and clues. Very nice puzzle!

[bristolrovers]

Started like a train and then about two thirds of the way through it all slowed to a struggle

[richardglover]

Amazing madness and great fun to watch.

[ThienNguyen]

29:33 what about 2348 in the first 4 cells of r1? r23 of c3 could be 15?

[siorac]

Yeah, took one look at the rules and noped out of this.

[srwapo]

I just couldn't wrap my head around how to use the logic in this puzzle. I got as far as finding the 1 and 9 in row 4. I would get stuck, skip ahead and see what the digits should be, see I was on the right track, but just not getting all the way there. I also messed up basic addition several times. I just gave up when I got to the 17 clue.

[ИгорьКравцов-дщ]

6:56 I don't understand the logic. What prevents 3 digits in cage 7 column 2 to be 2, 3, 4? 33 clue is fixing that afterwards, but question still remains