Dr. Sudoku Prescribes #25 – Masyu
or solve online (using our beta test of Penpa-Edit tools in linex mode where left click+drag draws lines and right click marks X’s)
Theme: Our 25th prescription! Enjoy this easy Masyu puzzle.
Answer String: Enter the length in cells of the horizontal loop segments from left to right in the marked rows, starting at the top. If the loop only has vertical segments in the marked row, enter 0. Separate each row’s entry with a comma.
Time Standard: Masyu Master = 0:30, Expert = 1:30, Novice = 5:00
Solution: PDF
I am happy to see this Masyu.
The reason is I was about to ask you to post Masyu and somehow I felt that you will post it soon so didn’t ask for it.
Nice start for beginners.
Hoping for a really hard Masyu this week.
1:00
Geez… I don’t think I could even COPY the solution in 30 seconds.
I obviously wrote a puzzle that took me 25 seconds, but my five testers went from 28 to about 40 seconds. So my guess is that the reflexes of the best puzzlers are just that much more trained, particularly in drawing loops.
At the Mystery Hunt I got a similar complaint, from a solver of the “puzzlemaster workout” book, where the best time of 3 seconds (which was mine; Palmer’s was 4 seconds) was described as completely ridiculous for one of the Simple Loops.
It took me 49 seconds, but that could just be a result of me doing these in poain. I am usually pretty good with loop puzzles so I’m looking foreward to see what you can throw at me on wednesday and friday. Personally, i think it is pretty hard to make a difficult masyu without using a variation.
Newcomers to the genre might try the sample problems at nikoli.com.
A few basic tips and tricks (there are lots, so these are just the basics).
1) Every black pearl has one horizontal and one vertical segment of length at least 2 coming from it. If one direction is impossible, draw it in the other (so all those black pearl that are one cell away from the edge or on the edge? draw a line towards the center). Another nice special case (that doesn’t happen in this puzzle) is if you have two black pearls next to each other, each has a segment pointing out away from the other pearl.
2) If you have three or more white pearls in a row (as happens in this puzzle), the paths through them must go transverse to the row (perpendicular to a line that passes through all of them). If you only have two white pearls in a row, the path could either go transverse through both (as it would with 3 or more), or go straight through both, but in that case it must turn on the ends.
3) White pearls on the edge of the puzzle. The path runs parallel to the edge, obviously. If there are two white pearls in a row on the edge, the path turns inward on both ends. If you have two with a single space between them on an edge, the path goes all the way through both of them and again turns inward on both ends. (Not so useful in this puzzle, but a common starting trick)
Maybe more tips later in the week as they crop up in puzzles
It took me 0:40 in Paint, so I think I could do it a bit quicker on paper. Definitely on the easy side of easy. Thanks for the puzzle, and I’m looking forward to later-in-the-week Masyus.
20 mins 27 s
Ohhh..I see some good starting tips here…Wish i had gone through the comments before i started solving but still after solving the puzzle i am able to understand the full impact of the tips with respect to the puzzle!
Who am I to look a gift horse in the mouth, BUT … any puzzle that I (a snail) can do under 40 seconds is not actually of much value. Mondays are throw-aways.
While I appreciate the luring in of others to the puzzle world, possibly a double on Monday is not asking too much. The best of both worlds would be a puzzle that beginniners can start easily, but then it gets to a point where slightly more advanced universal (full board) constraints are needed to complete.
As always, I thank you for your time in creating this great site. Just chiming in as you have requested.
TheSubro
Please don’t confuse your speed (“I’m a snail”) with your experience (you’ve solved hundreds of these by now). We all solve the same way generally, if just at different rates. Your issue is most likely with there being nothing new/challenging in the steps here, and that is an experience problem. I see a real purpose, particularly for someone’s “first ever Masyu” for a clean looking and clean solving puzzle. During this introduction phase, you may simply want to sit out Monday and Tuesday.
Seeing as the time above yours is over 20 minutes, I find it a stretch to say that the puzzle is not of much value to *anyone*. Even the simplest of deductions seem difficult if you’ve never tried the puzzle before. It was a good, smooth intro, not meant for the likes of you or I who can do most Masyu in our sleep.
1:40 Really, that’s a lovely Monday-level Masyu. Thanks!
2:02