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Binary Puzzle

binarypuzzle.com

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Re: Binary Puzzle

#21

Post by EvanKelly »

eldavojohn wrote: post #8
EvanKelly wrote: post #2

Oh Hi ( https://play.google.com/store/apps/details?id=com.presto.ohh... ) is an app I have that has these puzzles. Simple rules and can get surprisingly difficult.

What's the difference between your app (that has 100-500 downloads) and this app that has 100,000-500,000 downloads? https://play.google.com/store/apps/details?id=com.q42.ohhi&h...

Ha, oops, my wording was bad...I meant I had it on my phone...not my app and I just searched the app store. I'll change my link.

EDIT: No way to edit old posts, but the link I posted is obviously a rip-off of the Q42 app linked elsewhere.

Re: Binary Puzzle

#22

Post by jmull »

tome wrote: post #6

I wonder how one creates puzzles like this (or indeed creates Sudoku puzzles). I can think of a few strategies 1. Lovingly hand craft them. Extremely labour intensive! 2. Generate random grids and repeatedly remove elements. If that leads to a puzzle with more than one solution, backtrack. 3. Add random elements to an empty grid. Eventually the grid will have one or zero solutions. If zero, backtrack. If one, stop. F…

I've done this for Sudoku, cross sums and similar. Generally, I used a backtracking algorithm to fill an empty grid until a valid grid was found.

Assuming you want to control the level of difficulty of the puzzle generated, you want to incorporate the difficulty heuristics into the step-by-step filling-in algorithm (rather than just use them to score the puzzle after the fact).

Also, this probably should have been obvious, but at first I didn't do this: you get better control of the difficulty by basing your heuristics directly on the actual solving methods that people use. (If you don't somehow know already, you can, e.g., get a good book on solving sudoku which will enumerate the techniques and classify the difficulty as well. Once you understand the specific solving strategies for sudoku, you can probably generalize them to other logic puzzles.)

Re: Binary Puzzle

#23

Post by jmull »

alangpierce wrote: post #17

If anyone else was confused by the rule "No more than two similar numbers below or next to each other are allowed", I think it means that you aren't allowed to have three in a row of the same number, horizontally or vertically.

Yes, that's what I found.

(I too had trouble with that instruction.)

Re: Binary Puzzle

#24

Post by savanaly »

GrantSolar wrote: post #18

I feel that the rules should contain some examples. I spent a while battling a puzzle to realise that I had been interpretting "No more than two similar numbers next to or below each other are allowed." as "A box must have no more than 2 neighbours of each number" i.e. Exactly 2 0s and exactly 2 1s in the non-diagonal neighbours. I think that what's being referred to is runs of numbers, so if you see 0,0,_ you know t…

Yep, I made the exact same mistake. The hints have examples that disambiguate it which is how I found out in the end.

Re: Binary Puzzle

#25

Post by panic »

GrantSolar wrote: post #18

I feel that the rules should contain some examples. I spent a while battling a puzzle to realise that I had been interpretting "No more than two similar numbers next to or below each other are allowed." as "A box must have no more than 2 neighbours of each number" i.e. Exactly 2 0s and exactly 2 1s in the non-diagonal neighbours. I think that what's being referred to is runs of numbers, so if you see 0,0,_ you know t…

http://0hh1.com is a much better place to learn the rules.

Re: Binary Puzzle

#27

Post by cerebrum »

sushimako wrote: post #26

Very cool! It keeps saying that it's not solved correctly, but i cannot find the mistake: http://i.imgur.com/qPJLafH.png Already ironed out identical columns but can't seem to find anything else. Any idea?

1. and 6. row identical.

Re: Binary Puzzle

#28

Post by bluetwo »

zmonx wrote: post #4

The declarative programming language Prolog is a natural choice for solving such combinatorial tasks. Here is a Prolog formulation of the puzzle, using constraint logic programming over integers that ships with typical Prolog systems: binary_puzzle(Rows) :- length(Rows, L), maplist(same_length(Rows), Rows), maplist(only_two_next_to_each_other, Rows), transpose(Rows, Cols), maplist(only_two_next_to_each_other, Cols),…

I'm curious how long it would take to solve a hard puzzle using this technique. Anyone know?
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