Skyscrapers by Grant Fikes
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Theme: Logical
Author/Opus: This is the 152nd puzzle from our contributing puzzlemaster Grant Fikes.
Rules: Standard Skyscrapers rules.
Answer String: Enter the 5th row from left to right, followed by a comma, followed by the 4th column from top to bottom.
Time Standards (highlight to view): Grandmaster = 2:45, Master = 4:00, Expert = 8:00
Solution: PDF
Note: Follow this link for other classic Skyscrapers. If you are new to this puzzle type, here are our easiest Skyscrapers to get started on.
I hit a brick wall on this one. (I determined two digits. Then I found about 7 digits that had a choice of only two cells each. And I know a bunch of wider ranges for other cells. But I’m not sure how to proceed from here.)
I usually enjoy Skyscrapers, but with this one I’m feeling my sudoku curse taking over…
So I think you need to ask jung gur zvqqyr pryy bs gur yrsgzbfg pbyhza pna or, naq jurgure vg pna or frra sebz orybj.
Thanks for the tip, Jonah,
I took a second crack at this before reading any spoilers and it went much smoother the second time. You’re right about which cell unlocked the sticking point for me. I had clued into its importance the first time, but hadn’t fully carried out the implications.
If I haven’t said it before, let me say that I really appreciate the welcoming community of puzzle solvers and designers here at this website. It really is a pleasure to be able to learn from all of you. The concentration of talent here in one place is quite remarkable.
-Carl
I’m also hitting a hard contradiction on this. Here’s my logic so far:
Va pby bar, gur frira zhfg or bar bs gur gbc gjb pryyf va beqre gb nibvq oernxvat gur fvk pyhr. Vs vg jnf va ebj gjb, gura pby bar ebj sbhe unf ab jbexvat inyhr. Fb gung frira vf va gur gbc yrsg pbeare.
Abj ebj gjb’f frira zhfg or va pby gjb va beqre gb xrrc gung fvk pyhr nyvir, naq ebj guerr pby guerr zhfg nyfb or n frira gb xrrc gur svir pyhr nyvir.
Onpx gb pby bar sbe n zvahgr. Pby bar ebj sbhe zhfg or gur yvggyr ahzore gung vf abg frra ol gur fvk pyhr. Gung zrnaf pby bar ebj fvk vfa’g – vg unf gb or gjb be guerr. Ohg gur frira va ebj fvk pna’g or nal rneyvre guna pby sbhe. Jr pna fngvfsl gur gjb-pyhr va ebj fvk jvgu guerr gjb bar frira, ohg chggvat gur bar va ebj fvk pby guerr zrnaf gung pbyhza’f svir pyhr vf oebxra.
Lbhe ybtvp vf fbhaq fb sne. Ubjrire, lbh’er zvffvat fbzrguvat nobhg gur gjb pyhr. Vg pna tb guerr, gjb, bar, frira, be guerr, bar, gjb, frira. Vg qbrfa’g znggre gb gur guerr juvpu beqre gur bar naq gjb tb va, gurl whfg arrq gb or va fbzr beqre. Lbh’ir npghnyyl svtherq bhg juvpu jnl gurl tb! 🙂
Thanks.
There is no contradiction there as there is another way to satisfy the two clue in row six.
– Neelix
Number puzzles! My weakness! 10:56.
Am I the only one who works these in reverse? (Putting every number in each cell then removing possibilities until there is one left in each cell)
– Neelix
I do that sometimes, but I found it time consuming and it is not really readable.
How do you mark your grid for this technic ?
Keep in mind that I solve on the computer rather than with pen and paper which better lends itself to this technique.
In this case I used the text tool to create a block of centered numbers in rows of 2,3,2 in one of the cells, then copied and pasted that block to all the other cells. Then I used the pencil tool (set to white) with a brush just big enough to blot out a single number to erase the numbers I ruled out.
It means taking a bit of time for setup at the start, but once I’ve done that I find the puzzle solving itself much more straightforward.
– Neelix
I usually just put the maximum possible value in the corner of each cell, and changing that as I go. I put in the minimum as well if it isn’t 1. To be honest, I still find this to be slow, compared to the speed I solve other puzzles.
I try to keep the notation reasonable. I’ll mark possible locations for big numbers (in this puzzle you can put in all the 7’s pretty easily, but often you just have a pretty good idea roughly where the maximum numbers are). I’ll mark significantly restricted numbers (especially if it is down to 2 candidates, or 3 in a big puzzle like this). Really, I want my notation to draw my attention to the key logical steps, and if I notate everything in every square, my attention isn’t really drawn to anything.
I definitely have that problem, myself. Often when I get to the meat of a Latin-square-based puzzle I find myself over-notating every possibility. And rather than helping me, this often just obscures the essential piece of information that will help me make progress.
That was defintiely the case with this puzzle. Starting over with a clean sheet let me complete the puzzle where I had been stuck before. But I checked, and none of the notations I had made in the first failed attempt were incorrect. They just made too much noise for me.
17:39.Great skyscraper puzzle .Deciphering the difficult deductions were highly enjoyable.