Saturday 25 April 2020

Solution to Hidoku no 2

Hidoku no 2 (3 by 3)

Last night I changed my hidoku creation program so that it could produce puzzles from 3 by 3 up to 12 by 12. Here is a 3 by 3 puzzle, which is clearly very easy. You could perhaps work through it with a young child.

Here is a reminder of the rules. I arranged the numbers 1 through 9 in ascending order on the grid below before removing some of them at random. Your job is to replace the numbers I have removed. When you have finished, the grid must contain all the numbers 1 through 9 exactly once and cells with consecutive numbers must be joined horizontally, vertically or diagonally:



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Wednesday 22 April 2020

Jigsaw Crossword no 1

I saw a puzzle like this in a book and decided to create my own version. I copied an empty crossword puzzle from a well known newspaper onto squared paper. With a little help from Crossword Clue Solver I added my own set of words. Then I copied the grid into a table in Google Docs. I'm sure I could have used Microsoft Word instead but I don't have a copy of that. Finally, I split the puzzle up into 3x3 pieces and converted them into the images you can see below.

Fit the 3x3 pieces into the 15x15 grid underneath them to recreate a symmetrical crossword solution. The easiest way to do this is to print the page and cut the pieces out: 



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Saturday 18 April 2020

Solution to Sudoku no 520

Here is my original version of the solution:


...and here is another version from Rajkumar Ghosh, a member of the Sudoku Puzzles Facebook group. His picture has chopped off the right hand column but from the numbers I can see, he seems to have worked out the solution correctly:

Sudoku no 520 (Tough)

Play online

Sudoku grader and solver

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Thursday 16 April 2020

Hidoku no 1 (8 by 8)

I wrote a C program to arrange each of the numbers 1 through 64 in ascending order on the 8x8 grid below. Then I removed numbers at random and tested the remaining clues to see if they made up a hidoku puzzle with a unique solution. I did this using a Python program written by Rainhard Findling, which you can see here. If the puzzle was still valid I carried on. If it was not, I replaced the number I had just removed.

Your job is to replace the numbers I have removed. When you have finished, the grid must contain each of the numbers 1 through 64 exactly once and each number must be horizontally, vertically or diagonally adjacent to the numbers immediately above or below it



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Sunday 12 April 2020

Sunday 5 April 2020