📕Get my FREE Solving Guide that will help you solve over 80% of all Sudoku puzzles🧩to include NYT Hard👉👉www.buymeacoffee.com/timberlakeB/e/125822 Timestamps 0:00 Intro 00:17 It’s Solving Time 01:15 Tricky Solve 01:50 Puzzle Story 03:28 Solving Tip 06:18 Marking All Bivalue Cells 07:56 Setting Up Powerful Strategy 13:16 Finding Powerful Strategy Again 17:30 BONUS Advanced Strategy 19:22 Cleaning Up The Marks
I did the puzzle this morning, but didn't start the video until now. I got caught up in solving a freshman physics problem the hard, but conceptually correct, way and entering the solution into the computer. As usual with this puzzle, I filled out the grid and couldn't find anything other than bifurcating. Before that, I found a couple superfluous finned swordfish in 1s and 2s. They might have helped, near the end. I don't know. My first choice in bifurcating, I cornermarked the entire puzzle before noticing a collision. Centermarking the other choice got me nowhere, so I committed to the centermarked choice and found another bivalue cell to bifurcate on. This time, both choices served, and I finally solved the puzzle. 4:40 I only found the 12-pair in row 7 quite late -- when I noticed the quad while bifurcating. I also noticed (while bifurcating) a quint around the edges of block 1, the block with nothing.
Thank you for solving and making such a clear explainaition of the logic! I originally set this puzzle as a way for me to understand fireworks, and the underlying logic behind them; this puzzle definitely tests whether you can just spot a technique, or whether you really know what's going on. When I came across fireworks I realised that all the examples I'd seen only used three digits, but there was nothing that stopped you from having a four digit firework. With enough tinkering I managed to force a three digit into a four digit firework which felt very novel, and I'm very happy with how the break in to the puzzle turned out. Some of the later logic could've been signposted better, as I felt it was slightly unfair to spot the skyscraper in the middle of the grid. However because of how heavily constrained the puzzle already was, and my inexperience at setting, I decided that this was the best I could do at the time. It was quite difficult to design a finish to the puzzle without either breaking the forced fireworks, or requiring bifurcation. The skyscraper came out randomly while testing a few variations, and I thought it was too pretty to not include (even if it was evil to spot).
5:55, well, something obvious at this point are that r1c1, r1c9, and r9c1 must be selected from only the digits 123, given in c1 the only square outside b1 that can contain a 123 is in r9c1, and that in r1c9 the only place where a 123 can go outside b1 is r1c9, we can narrow down these spaces. That said, we can also declare these three cells, r1c1, r1c9, and r9c1, a triple selected from the digits 1, 2, and 3. We also know that r6c1 is a 78 and r1c4 is an 89.
At 6 min in I got the 89 in r1c4 and hunted for bent triples and empty rectangles (that I'm no good at seeing) Couldn't find any, nor any x- wings or swordfishes either, and having run out of tricks, then I came to see what you suggested.
📕Get my FREE Solving Guide that will help you solve over 80% of all Sudoku puzzles🧩to include NYT Hard👉👉www.buymeacoffee.com/timberlakeB/e/125822
Timestamps
0:00 Intro
00:17 It’s Solving Time
01:15 Tricky Solve
01:50 Puzzle Story
03:28 Solving Tip
06:18 Marking All Bivalue Cells
07:56 Setting Up Powerful Strategy
13:16 Finding Powerful Strategy Again
17:30 BONUS Advanced Strategy
19:22 Cleaning Up The Marks
I did the puzzle this morning, but didn't start the video until now. I got caught up in solving a freshman physics problem the hard, but conceptually correct, way and entering the solution into the computer. As usual with this puzzle, I filled out the grid and couldn't find anything other than bifurcating. Before that, I found a couple superfluous finned swordfish in 1s and 2s. They might have helped, near the end. I don't know.
My first choice in bifurcating, I cornermarked the entire puzzle before noticing a collision. Centermarking the other choice got me nowhere, so I committed to the centermarked choice and found another bivalue cell to bifurcate on. This time, both choices served, and I finally solved the puzzle.
4:40 I only found the 12-pair in row 7 quite late -- when I noticed the quad while bifurcating. I also noticed (while bifurcating) a quint around the edges of block 1, the block with nothing.
Thank you for solving and making such a clear explainaition of the logic!
I originally set this puzzle as a way for me to understand fireworks, and the underlying logic behind them; this puzzle definitely tests whether you can just spot a technique, or whether you really know what's going on. When I came across fireworks I realised that all the examples I'd seen only used three digits, but there was nothing that stopped you from having a four digit firework. With enough tinkering I managed to force a three digit into a four digit firework which felt very novel, and I'm very happy with how the break in to the puzzle turned out. Some of the later logic could've been signposted better, as I felt it was slightly unfair to spot the skyscraper in the middle of the grid. However because of how heavily constrained the puzzle already was, and my inexperience at setting, I decided that this was the best I could do at the time. It was quite difficult to design a finish to the puzzle without either breaking the forced fireworks, or requiring bifurcation. The skyscraper came out randomly while testing a few variations, and I thought it was too pretty to not include (even if it was evil to spot).
5:55, well, something obvious at this point are that r1c1, r1c9, and r9c1 must be selected from only the digits 123, given in c1 the only square outside b1 that can contain a 123 is in r9c1, and that in r1c9 the only place where a 123 can go outside b1 is r1c9, we can narrow down these spaces. That said, we can also declare these three cells, r1c1, r1c9, and r9c1, a triple selected from the digits 1, 2, and 3. We also know that r6c1 is a 78 and r1c4 is an 89.
At 6 min in I got the 89 in r1c4 and hunted for bent triples and empty rectangles (that I'm no good at seeing) Couldn't find any, nor any x- wings or swordfishes either, and having run out of tricks, then I came to see what you suggested.
SLot machine on 1 and 2....
Thank you for pointing that out, Roger.