The proper logic for determining of 7/8 is this - R7C8 is either green (9) or yellow (8). The blue line in box 6 must have a 1 (since there are 2 4s looking at it) and not have 6, so it's either 125 or 135. R5C7 can't be a 1. If R7C8 is 8 (yellow), the blue line in box 6 is 125 and R5C7 becomes 3, forcing red to also be 8. Therefore, R7C8 must be 9 and then go from there
You need to be very very careful when colouring, in this case the orange 89 pair in box 9 was not useful and confused Mark into a wrong deduction. If anyone knows the way forward please elaborate, the mistake happens at 21:40
Assuming you've got most cells pencil marked by this point - Once you've got your possible red and yellows in place - check R7C8, and see if placing a number causes any issues with the digits on the green line that spans Box 2>Box 6.
From 21:40, if you explore the option of R7C8 being an 8, it forces R7C2 (red) to be "7" and the blue equal-sums line in box 6 to be "1-2-5" (since 1-3-4 isn't possible by the two 4s already in rows 5 and 6), this then leaves R5C7 to be "3" as the only option remaining. This "3" on a German Whispers green line pushes R4C6 (red) to be "8". Since R7C2 and R4C6 are both marked red (correctly by Mark), we have reached a contraction as red cannot be both "7" and "8". Therefore R7C8 must instead be "9". This doesn't immediately determine the colouring at the bottoms of columns 5 and 8 but there is more colouring to be completed in the rest of the grid. The "9" forces "1-3-5" on to Box 6's blue equal-sums line, leaving yellow ("7" or "8") to only be possible in the top row of Box 6 and thus also in R6C2 in Box 4 (as it can't be on the whisper since this is low in R6C3). The "1-3-5" in Box 6 also forces the "2" onto R5C7. Mark hasn't yet resolved the pencil marking in Box 8, which is now "1-3-5" down the left side and "2" and "4" on the right. The "2"s positioning in Box 6 and Box 8 forces R4C5 to be a "2". and, in turn, R6C3 to also be "2". This then means R8C3 is now a "3" separating an 8 and 9 (on the whisper) at the bottom of column 3 thus giving you that "7" is red and "8" is yellow. I'm allowing Mark a wine click given it's Christmas Eve!
I got a lot more of the puzzle done by colouring cells 'high' (6789) and 'low' (12345) before resolving the 7 and 8s. I used bifurcation to get the 6s on the blue lines. I finally used colouring and bifurcation again to resolve the 7 and 8s.
*_"Red_*_ is definitely in one of those two [r9c7 or r8c8]..."_ (Mark @21:16) Incorrect. It is either in *r8c8* or *r9c8.* _"... so if it cannot go there [r9c7],it must be this [r8c8]"_ (Mark @21:38) Correct conclusion reached with incorrect logic. You did not rule out *r9c8❗* You missed the most enjoiable part of the solve, which was the final disambiguation for the *7-8* pair.
@@debrawilden1971 I'm not sure if that answers the question, though. Sure, you can get 9 out of that cell, but you can't get red out of there at this point in the solve - red is 7 or 8, so determining R9C8 is an 8 doesn't tell you whether it's red or not.
Assuming you've got most cells pencil marked by this point - Once you've got your possible red and yellows in place - check R7C8, and see if placing a number causes any issues with the digits on the green line that spans Box 2>Box 6.
The rule on reguin sum line in this puzzle is incorrect. Classical ruling should be applied instead: Blue region sum line is split into segments by 3x3 box borders. Each segment along the line should have the same total, but different lines may have different totals.
wow, I've never done 80% of a puzzle so quickly, only to grind to a half in the last 20%. 40ish minutes in the end, and I cracked the 7s and 8s a totally different way than Marc, which surprised me.
I finished in 22:30 minutes. This was a really clean puzzle that perfectly executed region sum rules. That was one of the most fun kind that I have done. I think my favorite part was seeing that the region sum in box 6 couldn't be 8 with a 125 set as this causes a cascade that would force both r9c3 and r9c8 to both be the same number. That was so fun to spot in my head. This has to be one of my favorites. As always, it feels good to beat Mark's time. Great Puzzle!
Great construction. I needed separate colours only for *7-8* pairs at the end. 5 was white. Everything else was *blue* or *orange* to represent polarity. By the way, the final disambiguation of the *7-8* pairs was perhaps the most enjoyable part of my solve and Mark missed it because he used incorrect logic to reach the same result, as I explained in a separate comment.
What is the proper method forward at 21:41? Mark's spouting nonsense at this point, as if red is not 7 it is 8, and that just means c8 in b9. Is bifurcation required to solve?
If you look at the 2-3 pair in box 6 attached to the German Whisper, if it is a 3 then "red" (in Mark's puzzle) is an 8. However, if it is a 3 then the region sum line in box 6 will sum to 8. That is a contradiction since the number attached to the region sum line in box 9 is not red.
*LOGICAL FALLACY* - 21:17 - Red could have been an '8' if it were in (Row 9, Col 8) = We *DEMAND* an apology...! LOL... We *DEMAND* perfection from Mark "Beast-Mode" Goodliffe...!
I did quite well up until near the end, got stuck and bifurcated on a hunch which actually worked out. 😛 Mark's coloring of the high would have shown me what I needed, but still managed to finish in 19:38 (conflict checker off), many thanks to James for a very nice puzzle!
Christmas finery, Christmas in the puzzle, all very fun. I don't have time to try this puzzle now, but will definitely do so soon. This was an interesting puzzle; I like the interactions between the blue and green lines. Thanks for the video, Mark, and a very Merry Christmas to you and yours!
Rules: 02:23 Let's Get Cracking: 02:58 What about this video's Top Tier Simarkisms?! Three In the Corner: 1x (28:37) And how about this video's Simarkisms?! Ah: 8x (09:34, 11:44, 14:45, 18:02, 18:05, 18:45, 19:08, 27:57) In Fact: 4x (15:12, 16:29, 17:01, 20:37) Brilliant: 3x (00:48, 02:07, 28:40) By Sudoku: 3x (09:41, 27:21, 27:24) Obviously: 3x (00:44, 16:16, 19:27) Pencil Mark/mark: 3x (07:39, 25:12, 28:15) Naked Single: 1x (24:26) Lovely: 1x (24:37) Extraordinary: 1x (17:11) First Digit: 1x (10:01) Deadly Pattern: 1x (26:20) Hang On: 1x (27:42) Most popular number(>9), digit and colour this video: Thirty Five (4 mentions) One (79 mentions) Red (43 mentions) Antithesis Battles: High (15) - Low (11) Even (2) - Odd (0) Column (15) - Row (12) FAQ: Q1: You missed something! A1: That could very well be the case! Human speech can be hard to understand for computers like me! Point out the ones that I missed and maybe I'll learn! Q2: Can you do this for another channel? A2: I've been thinking about that and wrote some code to make that possible. Let me know which channel you think would be a good fit!
I got stuck on the 7-8's and came to the video for a solution. Was disappointing to see Mark solving from what I understand was a lucky guess. Surely the 8 below the 7 in box 9 could also have been red? Amyway, happy holidays to all!
About the R9C8 controversy: I was able to desambiguate with A LOT of backtracking after assumptions. I don't know how Mark got it that fast without being confused by his own pencil marks.
Merry Christmas, or what is left of it. I think I had made a big mistake, but it turned out to be small... I had mislabeled 8 and 9 in boxes 7 and 9. After fixing that I was able to finish swiftly.
117:49, broke the puzzle twice, looked at the video, saw that I ruled a 4 out of r7c6 at like the beginning because a 4 can't be in the middle of a green line (🤦♂️) and had to redo the puzzle. Of course, I mistyped a digit part way through and had to go through most of it a third time.
The Description of the blue line is wrong. BOX 7 would have 4 numbers that the blue line visits and those sum at least to 10. Extra text needed like 'distinct groups on the same blue line count as different groups for the sum' .
I think the rules, while a bit awkward, do indicate 'the same total in each 3x3 box the line visits.' This means that every time the line enters the box, it will have the same total. It's not the sum of ALL the blue lines in the box that = the sum of the connected blue lines in another box. (In box 7, the line in C = R6C1 = R7C2.) (I know this to be the case because I've seen a lot of puzzles with this rule. The puzzling time is when the blue line is only in one box. That has happened and makes no sense! At that point, I think it's just cosmetic, but certainly leads to confusion.)
The text in the video and the description say "box borders divide the line into equal sum segments", which makes it clear. The rules in the puzzle itself is the less clear version, which sometimes tries to mean the equivalent to that, and sometimes means add all the segments together. Since it is impossible for 4 different cells to add to a single cell, it is clear that the alternate version used in the video and the description is correct. I think it is hard to edit the rules in an existing puzzle without making a new link and "resetting" the solution count for the puzzle.
Follow the usual solve process until you get stuck, and then look at the arrow clue that spans Box 9>Box 6 - there's a break in logic that doesn't require bifurcation to spot
The proper logic for determining of 7/8 is this - R7C8 is either green (9) or yellow (8). The blue line in box 6 must have a 1 (since there are 2 4s looking at it) and not have 6, so it's either 125 or 135. R5C7 can't be a 1. If R7C8 is 8 (yellow), the blue line in box 6 is 125 and R5C7 becomes 3, forcing red to also be 8. Therefore, R7C8 must be 9 and then go from there
"R5C6 can't be a 1" - citation needed!
If r7c8 is 8 then it is yellow. But this forces r5c7 to be 3 which forces red (in box 5) to be 8!
@@peaoui165it might be R5C7, not R5C6. The previous statement says 1 is on the blue line, thus 1 cannot be in R5C7.
Thank you! That's exactly where I got stuck. And yes R5C6 is a typo it's R5C7 that can't be 1 at that point.
@@peaoui165 sorry, meant R5C7, will correct. Thank you for noticing
You need to be very very careful when colouring, in this case the orange 89 pair in box 9 was not useful and confused Mark into a wrong deduction. If anyone knows the way forward please elaborate, the mistake happens at 21:40
With bifurcation (trying out the WRONG path, to see what conflict arises) I ended up with a 3 adjacent to a 7 on the bottom right leg of the X.
Assuming you've got most cells pencil marked by this point -
Once you've got your possible red and yellows in place - check R7C8, and see if placing a number causes any issues with the digits on the green line that spans Box 2>Box 6.
From 21:40, if you explore the option of R7C8 being an 8, it forces R7C2 (red) to be "7" and the blue equal-sums line in box 6 to be "1-2-5" (since 1-3-4 isn't possible by the two 4s already in rows 5 and 6), this then leaves R5C7 to be "3" as the only option remaining. This "3" on a German Whispers green line pushes R4C6 (red) to be "8". Since R7C2 and R4C6 are both marked red (correctly by Mark), we have reached a contraction as red cannot be both "7" and "8". Therefore R7C8 must instead be "9". This doesn't immediately determine the colouring at the bottoms of columns 5 and 8 but there is more colouring to be completed in the rest of the grid. The "9" forces "1-3-5" on to Box 6's blue equal-sums line, leaving yellow ("7" or "8") to only be possible in the top row of Box 6 and thus also in R6C2 in Box 4 (as it can't be on the whisper since this is low in R6C3). The "1-3-5" in Box 6 also forces the "2" onto R5C7. Mark hasn't yet resolved the pencil marking in Box 8, which is now "1-3-5" down the left side and "2" and "4" on the right. The "2"s positioning in Box 6 and Box 8 forces R4C5 to be a "2". and, in turn, R6C3 to also be "2". This then means R8C3 is now a "3" separating an 8 and 9 (on the whisper) at the bottom of column 3 thus giving you that "7" is red and "8" is yellow. I'm allowing Mark a wine click given it's Christmas Eve!
I got a lot more of the puzzle done by colouring cells 'high' (6789) and 'low' (12345) before resolving the 7 and 8s. I used bifurcation to get the 6s on the blue lines. I finally used colouring and bifurcation again to resolve the 7 and 8s.
*_"Red_*_ is definitely in one of those two [r9c7 or r8c8]..."_ (Mark @21:16)
Incorrect. It is either in *r8c8* or *r9c8.*
_"... so if it cannot go there [r9c7],it must be this [r8c8]"_ (Mark @21:38)
Correct conclusion reached with incorrect logic. You did not rule out *r9c8❗*
You missed the most enjoiable part of the solve, which was the final disambiguation for the *7-8* pair.
21:17 How its possible R9C7 to be red? Why it is a candidate? R89C8 is candidates
21:13 Why can red not be in R9C8 here exactly?
Not sure exactly where you are in the solve, but I got R9C8 by seeing the blue lines in box 6 adding to 9.
@@debrawilden1971 I was the at a point where they could still be either 8 or 9, 125 or 135
so couldn't use that yet
@@debrawilden1971 I'm not sure if that answers the question, though. Sure, you can get 9 out of that cell, but you can't get red out of there at this point in the solve - red is 7 or 8, so determining R9C8 is an 8 doesn't tell you whether it's red or not.
@@Samoth1995 (Sorry I can't help further. I didn't follow the whole video, and I used diff colors then deleted them when all use.)
Assuming you've got most cells pencil marked by this point -
Once you've got your possible red and yellows in place - check R7C8, and see if placing a number causes any issues with the digits on the green line that spans Box 2>Box 6.
The rule on reguin sum line in this puzzle is incorrect. Classical ruling should be applied instead: Blue region sum line is split into segments by 3x3 box borders. Each segment along the line should have the same total, but different lines may have different totals.
I really dislike box being counted as one segment without calling it out
wow, I've never done 80% of a puzzle so quickly, only to grind to a half in the last 20%. 40ish minutes in the end, and I cracked the 7s and 8s a totally different way than Marc, which surprised me.
I finished in 22:30 minutes. This was a really clean puzzle that perfectly executed region sum rules. That was one of the most fun kind that I have done. I think my favorite part was seeing that the region sum in box 6 couldn't be 8 with a 125 set as this causes a cascade that would force both r9c3 and r9c8 to both be the same number. That was so fun to spot in my head. This has to be one of my favorites. As always, it feels good to beat Mark's time. Great Puzzle!
Merry Christmas, Mark! Thanks for all you do.
Great construction.
I needed separate colours only for *7-8* pairs at the end. 5 was white. Everything else was *blue* or *orange* to represent polarity.
By the way, the final disambiguation of the *7-8* pairs was perhaps the most enjoyable part of my solve and Mark missed it because he used incorrect logic to reach the same result, as I explained in a separate comment.
37:46 for me. I messed up the puzzle, but was able to salvage it. Now I'm off to Christmas Eve church service. Merry Christmas, all!!
Pretty sure red could also be at r9c8.
came looking for this kind of comment
What is the proper method forward at 21:41? Mark's spouting nonsense at this point, as if red is not 7 it is 8, and that just means c8 in b9.
Is bifurcation required to solve?
If you look at the 2-3 pair in box 6 attached to the German Whisper, if it is a 3 then "red" (in Mark's puzzle) is an 8. However, if it is a 3 then the region sum line in box 6 will sum to 8. That is a contradiction since the number attached to the region sum line in box 9 is not red.
Ah, yes, if r5c7 is a 3, both r7c2 and r7c8 have to be 8, and that is a contradiction. I see now.
*LOGICAL FALLACY* - 21:17 - Red could have been an '8' if it were in (Row 9, Col 8) = We *DEMAND* an apology...! LOL... We *DEMAND* perfection from Mark "Beast-Mode" Goodliffe...!
I did quite well up until near the end, got stuck and bifurcated on a hunch which actually worked out. 😛 Mark's coloring of the high would have shown me what I needed, but still managed to finish in 19:38 (conflict checker off), many thanks to James for a very nice puzzle!
Man I'm stuck on the puzzle and while trying to figure out what I should find on the video I instead see wrong logic to solve the puzzle.
Finished in 25:56. Great puzzle!
Sounds like my xmas dinner, fun, a little bit of crunch, and satisfaction at the end
You look nice, Mark! Merry Christmas everyone!!
Christmas finery, Christmas in the puzzle, all very fun. I don't have time to try this puzzle now, but will definitely do so soon. This was an interesting puzzle; I like the interactions between the blue and green lines. Thanks for the video, Mark, and a very Merry Christmas to you and yours!
I can confirm. It's a beautiful sunny Christmas Day down here in Australia.
Merry Christmas to you and Simon!
Nice fireplace in the back ;) Merry Christmas, Mark!
Rules: 02:23
Let's Get Cracking: 02:58
What about this video's Top Tier Simarkisms?!
Three In the Corner: 1x (28:37)
And how about this video's Simarkisms?!
Ah: 8x (09:34, 11:44, 14:45, 18:02, 18:05, 18:45, 19:08, 27:57)
In Fact: 4x (15:12, 16:29, 17:01, 20:37)
Brilliant: 3x (00:48, 02:07, 28:40)
By Sudoku: 3x (09:41, 27:21, 27:24)
Obviously: 3x (00:44, 16:16, 19:27)
Pencil Mark/mark: 3x (07:39, 25:12, 28:15)
Naked Single: 1x (24:26)
Lovely: 1x (24:37)
Extraordinary: 1x (17:11)
First Digit: 1x (10:01)
Deadly Pattern: 1x (26:20)
Hang On: 1x (27:42)
Most popular number(>9), digit and colour this video:
Thirty Five (4 mentions)
One (79 mentions)
Red (43 mentions)
Antithesis Battles:
High (15) - Low (11)
Even (2) - Odd (0)
Column (15) - Row (12)
FAQ:
Q1: You missed something!
A1: That could very well be the case! Human speech can be hard to understand for computers like me! Point out the ones that I missed and maybe I'll learn!
Q2: Can you do this for another channel?
A2: I've been thinking about that and wrote some code to make that possible. Let me know which channel you think would be a good fit!
Pretty sure you missed his mistake at 21:17, and him getting lucky.
Wishing you and your family a Merry Christmas
26:09 ... a nice solve for Christmas Eve
Nice puzzle!
What song is the into music from??
I got stuck on the 7-8's and came to the video for a solution. Was disappointing to see Mark solving from what I understand was a lucky guess. Surely the 8 below the 7 in box 9 could also have been red? Amyway, happy holidays to all!
About the R9C8 controversy: I was able to desambiguate with A LOT of backtracking after assumptions. I don't know how Mark got it that fast without being confused by his own pencil marks.
lookin' fine, mark!
14:53 a nice, quick, and easy Xmas Eve puzzle!
26:12 finish. Merry Christmas to all!
Don t forget the given 4 in box 4 😉
Merry Christmas, and a very happy day if you don’t celebrate Christmas. Gorgeous jacket, Mark!
You can get pretty far w/o givens but seems like the 3 givens dissolve 3 different cluster of cells
Another lucky placement!
I was just wanting to look for a nicer way of placing 78 than I have used.
Mark's pencil marking is simply hopeless in this one...
63:36 for me, after missing some very obvious sudoku
80m for me. A fun and festive solve
Merry Christmas, or what is left of it.
I think I had made a big mistake, but it turned out to be small... I had mislabeled 8 and 9 in boxes 7 and 9. After fixing that I was able to finish swiftly.
117:49, broke the puzzle twice, looked at the video, saw that I ruled a 4 out of r7c6 at like the beginning because a 4 can't be in the middle of a green line (🤦♂️) and had to redo the puzzle. Of course, I mistyped a digit part way through and had to go through most of it a third time.
24:40 for me
nice puzzle
00:54:51
34.01 for me
25:50 for me.
The Description of the blue line is wrong. BOX 7 would have 4 numbers that the blue line visits and those sum at least to 10. Extra text needed like 'distinct groups on the same blue line count as different groups for the sum' .
I think the rules, while a bit awkward, do indicate 'the same total in each 3x3 box the line visits.' This means that every time the line enters the box, it will have the same total. It's not the sum of ALL the blue lines in the box that = the sum of the connected blue lines in another box. (In box 7, the line in C = R6C1 = R7C2.)
(I know this to be the case because I've seen a lot of puzzles with this rule. The puzzling time is when the blue line is only in one box. That has happened and makes no sense! At that point, I think it's just cosmetic, but certainly leads to confusion.)
The text in the video and the description say "box borders divide the line into equal sum segments", which makes it clear. The rules in the puzzle itself is the less clear version, which sometimes tries to mean the equivalent to that, and sometimes means add all the segments together. Since it is impossible for 4 different cells to add to a single cell, it is clear that the alternate version used in the video and the description is correct. I think it is hard to edit the rules in an existing puzzle without making a new link and "resetting" the solution count for the puzzle.
"box borders divide the line into segments" - so we know that there are 2 different segments in box 7.
Nice. 25:28 for me
36:41 for me and solver #1746.
Not a great solve Mark
You did an error in concluding that red had to be 7, that’s not proper logic
BTW solved it in 25 mins 23 secs with proper logic
19:46 for me. not happy. i missed one line that made me waste a lot of time.
Seems this can't be solved without bifurcation. Thumbs down
Follow the usual solve process until you get stuck, and then look at the arrow clue that spans Box 9>Box 6 - there's a break in logic that doesn't require bifurcation to spot
I solved this without any plug and chug at all.
If r5c7 is a 3, it provides an instant contradiction between r7c2 and r7c8.
00:38:43
26:41 for me