The New Sudoku Players' Forum

[joe94]

Published sudoku puzzles often have more than one solutions. Dubbing such puzzles cannot be verified by the program because they are not valuable puzzle in terms of the program. There should be a key to allow to play such puzzles

[Hud]

I think so too. They're a lot easier to solve on the computer than on paper even if they can't be verified or checked.

[Pi]

the thing with multiple solution puzzles is that they are essentially impossible.

that is you will always reach a point when guessing is required. My advice is that if you think your puzzle may have more than one solution to brute force it using some software and see if it is valid.

It is not worth trying to solve a puzzle with multiple solutions.

I have never seen a Pappocom puzzle with more than one solution (other than one from the Times national championship which was an error by the newspaper) . I recommend you use these.If you have the program you have a huge supply of them anyway

[Spok]

I have long since 'outgrown' the program's 'Very Hard' puzzles. Practice has me doing these in about ten minutes. So I want a bigger challenge. I have tried dubbing in some extremely hard puzzles to solve on the computer. I really like the interface of this program and find solving with it a joy. I like to do all the solving work myself, with no Hints to assist me. How ever, when I come to verify these extremely hard puzzles, the program says they are not valid and I get no further. But I know these puzzles are valid in that they have only one solution and do not require any guessing.

Please can the program be changed so it will let me solve any puzzle I enter, even if it thinks, and has warned me, that it is invalid.

Spok.

[MacKaiwer]

the thing with multiple solution puzzles is that they are essentially impossible.

that is you will always reach a point when guessing is required. My advice is that if you think your puzzle may have more than one solution to brute force it using some software and see if it is valid.

It is not worth trying to solve a puzzle with multiple solutions.

I have never seen a Pappocom puzzle with more than one solution (other than one from the Times national championship which was an error by the newspaper) . I recommend you use these.If you have the program you have a huge supply of them anyway

<------I agree all that Pi said but I am sick and tired off sudokus in which one must go guessing in some point off the game... I have tested Gamehouse sudoku, Sudoku starlet and Pappocom sudoku and in everyone of those Pc programs I had faced situation where I must guess next right number and it's not possible continue with logic... That's get me p***** [Edited by Luna] and angry... And I was thinking that sudokus are peaceful and relaxing games!!! In paper sudokus are same problems too... I think I will stop playing sudokus because You can never be sure is this game solid or just some guessing play again! (I hope I put it all clear enough to understand because english is not my strongest language...)

[lunababy_moonchild]

<------I agree all that Pi said but I am sick and tired off sudokus in which one must go guessing in some point off the game... I have tested Gamehouse sudoku, Sudoku starlet and Pappocom sudoku and in everyone of those Pc programs I had faced situation where I must guess next right number and it's not possible continue with logic...

I can't speak for Gamehouse Sudoku or Sudoku Starlet but I do know that Pappocom doesn't make a puzzle where it's necessary to guess, they are all one solution solvable by logic puzzles. Perhaps you need to review your solving techniques or go down to an easier playing level.

That's get me p***** [edited by Luna] and angry... And I was thinking that sudokus are peaceful and relaxing games!!! In paper sudokus are same problems too... I think I will stop playing sudokus because You can never be sure is this game solid or just some guessing play again! (I hope I put it all clear enough to understand because english is not my strongest language...)

You don't say what country you are in, I suspect that it's America, but the word I just edited isn't appropriate for this Forum (it means something different in Great Britain, for example). That said, I can't vouch for every newspaper puzzle but, again, when it comes to Pappocom, guessing isn't necessary whichever level you're on.

In my opinion, perhaps you should browse the Forum and make yourself familiar with the solving techniques.

Luna
Moderator

[MacKaiwer]

My bad, I'm sorry for my output and dirty language... I am from Finland. Maybe there is something to learn and to do better in my sudoku solving techniques, but if in sudoku one must take a guess then that one may be not checked and not verified, am I right? Maybe I am wrong with my opinion of Pappocom Sudoku, (I have played with that program only two games, might be overreacting), maybe I did a mistake or was not concentreating good enough, maybe your program is errorless, but still my opinion is that pc sudoku programs do mistakes in their games and then You must guess in some point of game... They are still doing random selection when making new game and all of them may not check and verify properly the result... I might not be the best sudoku player but I'm not so bad either and I think I might be partly right with my opinion that pc's and their programs are not always right in what they do!

But with all respect, I'm not perfect human being, I might be wrong and therefor I admit my mistakes and ask your forgivness

[lunababy_moonchild]

....... but if in sudoku one must take a guess then that one may be not checked and not verified, am I right?

That's right and that's why guessing is frowned upon by most regular sudoku players.

Maybe I am wrong with my opinion of Pappocom Sudoku, (I have played with that program only two games, might be overreacting), maybe I did a mistake or was not concentreating good enough, maybe your program is errorless,

Pappocom's program is not my program specifically, it was written by Wayne Gould who also administers this Forum. I have used his program extensively, for at least a year, (if not more, I can't actually remember!) and I can say with confidence that I've never met a puzzle that required guessing.

but still my opinion is that pc sudoku programs do mistakes in their games and then You must guess in some point of game... They are still doing random selection when making new game and all of them may not check and verify properly the result... I might not be the best sudoku player but I'm not so bad either and I think I might be partly right with my opinion that pc's and their programs are not always right in what they do!

But with all respect, I'm not perfect human being, I might be wrong and therefor I admit my mistakes and ask your forgivness

You are entitled to your opinion and are welcome to express it, carefully , and of course, forgiven.


You can, of course, post any puzzle you're having trouble with - in the 'Help with particular puzzles' section you'll find all the information you need to do this and (conveniently!) that's the section you post the particular puzzle you're having trouble with. There is always someone who is willing to point out the very next step to you and in beginner's language.

Luna
Moderator

[MacKaiwer]

My final statement to this matter... I played few games more with Pappocom Sudoku (easy and medium level) and they all solved reliable, smooth and correct, no problem <-----conclusion, hard level was too hard to me to begin with and I made wrong picture in my head that program was doing something false, no, it's good and solid sudoku program (I like very much that I can print sudoku and take it with me when I'm leaving from computer for some time...)! I was just overtired, playing first time in the middle of the night, making some mistakes at too hard level for beginner and then frusthtrated...

But it feels good to admit that I was wrong

Sudoku is still cool game and that's all!

Thanks Luna!

[Son of Pappocom]

hard level was too hard to me to begin with and I made wrong picture in my head that program was doing something false

Don't worry MacKaiwer, happens all the time! Keep at it and you'll be able to get through Hard puzzles as quickly as you do Easy ones now.

Regards
Scott

[Cec]

".. I was just overtired, playing first time in the middle of the night, making some mistakes at too hard level for beginner and then frusthtrated...

But it feels good to admit that I was wrong

Sudoku is still cool game and that's all!

Thanks Luna!

I just had to express my appreciation to MacKaiwer's honesty and to others participating in this enlightening Thread - You've all "made my day"
Cec

[Sudoku Master2]

Published sudoku puzzles often have more than one solutions. Dubbing such puzzles cannot be verified by the program because they are not valuable puzzle in terms of the program. There should be a key to allow to play such puzzles

Yeah. Only a few puzzles have one solution.

Well, actually, I have this Sudoku book called Junior Su Doku, and every puzzle so far that I've done has one solution.

[beetjepeetje]

Well, IF a sudoku has only one solution (otherwise it is not a real sudoku) then there should be SOME rule(s) to get to this solution without guessing. However these rules might be too complex for humans to see.

The SudokuExplainer programmers say to have no sudokus seen that cannot be solved using the -sometimes quite complex- rules it uses.
(see http://diuf.unifr.ch/people/juillera/Sudoku/Sudoku.html )

In fact, there are quite some rules that SudokuExplainer uses like: IF we put certain number there, THAN we get something unsolvable at onother place, so that certain number there is not possible. One could say this is a kind of guessing and backtracking.. However, these 'what-if' rules are
moderately easy to see through, so we do not call it guessing but e.g.
smart thinking...

So, to my opinion, some level of guessing is not bad practice, at least
until you are an expert (and I'm not).