Sliding Number Puzzle

**Pete_UK** · 10-27-2014, 10:22 PM

Just to comment on your number 1:

Years (and years) ago (in the 1980's) I wrote a program to generate sliding block puzzles on a 3 x 3, 4 x 4 or 5 x 5 grid (user-selectable - I used letters of the alphabet, so couldn't allow it to be bigger), and I just generated a number of random moves to begin with. This did create unwinnable situations. I got round it by generating random numbers in the range 1 to 4 where each number represented a direction (up/down, left/right) and effectively moved a tile into the "blank" from those directions.

As for who designed it (your number 6), I remember playing with a plastic version when I was a kid in the 60's, so I think the game has a very long history.

Hope this helps.

Pete

**mc84excel** · 10-28-2014, 03:46 AM

Originally Posted by Pete_UK

Years (and years) ago (in the 1980's) I wrote a program to generate sliding block puzzles on a 3 x 3, 4 x 4 or 5 x 5 grid (user-selectable - I used letters of the alphabet, so couldn't allow it to be bigger), and I just generated a number of random moves to begin with. This did create unwinnable situations. I got round it by generating random numbers in the range 1 to 4 where each number represented a direction (up/down, left/right) and effectively moved a tile into the "blank" from those directions.

I had a vague idea that truly random shuffles (as opposed to doing a number of random but valid moves) could create unwinnable situations in sliding block puzzles. Thanks for confirming it.

BTW slightly off-topic but have you made any sliding block puzzles in Excel? I'd be interested in seeing it if that's OK with you.

Originally Posted by Pete_UK

As for who designed it (your number 6), I remember playing with a plastic version when I was a kid in the 60's, so I think the game has a very long history.

That's interesting. Someone has recently pointed out to me one made by Binary Arts and it's called Top Spin (TopSpin? Top-Spin?). I googled Top Spin and the pictures are the same as the one I saw. Is the same as the one you saw?