Bug 349583

Summary: Solver gives wrong information
Product: [Applications] kpat Reporter: KOLI <karola.bvb>
Component: solverAssignee: Stephan Kulow <coolo>
Status: RESOLVED FIXED    
Severity: normal CC: kde-games-bugs-null, MarathonToo
Priority: NOR    
Version First Reported In: 3.6   
Target Milestone: ---   
Platform: Ubuntu   
OS: Linux   
Latest Commit: Version Fixed In:
Sentry Crash Report:

Description KOLI 2015-06-24 21:59:48 UTC 
The solver in the game Großvater (German version) (e.g. game number 1914956398) claims that the game is not winnable, but after redaeling cards it is possible to win the game.
This has been observed in several games of this type.

Reproducible: Sometimes

Steps to Reproduce:
1. call up game no. 1914956398
2. play until hints are exhausted
3. redeal and go on playing

Actual Results:  
now the game is winnable

Expected Results:  
The software should have to know the correct result from the start.
Comment 1 James Funk 2018-11-27 02:30:04 UTC 
In a Freecell game, I reached a state in which the solver in the bottom left of the screen said "this game is winnable", but every time I made a non-reversible move, the solver said "this game is no longer winnable."  Eventually, I gave up, and clicked the "demo". After a few moves, the demo made an illegal move, placing a red 3 on a black 9. I undid some moves and ran the demo again. This time, after a few moves, the demo entered a cycle in which the sequence of states of the game were duplicated. I did this twice. The first time, the cycle was very short: It moved a red queen back and forth between two black kings.

I am not able to give the steps to reproduce this, because, in this version, the game number is not available. In previous versions, the game number appeared on the window title bar. :-( 

I just tried the demo again. This time, after many moves, it placed a black 8 on a black 8.  

The solver has always been reliable before.
Comment 2 James Funk 2018-11-29 03:00:16 UTC 
I wish my comment to be considered withdrawn. I recalled that I had taken a break during that game, and saved it. In loading that file, I cannot recreate the software errors I reported.

I played some moves and clicked the "demo" button a few times. I never did catch it making an illegal move. It did solve the game, but it took over 500 moves. There were some strange sequences, such as moving a red 2 from a black 3 to a free cell, and then moving the other red 2 from a free cell to the black 3. Inefficient, but not illegal.
Comment 3 Christoph Feck 2018-12-20 15:51:00 UTC 
KPat is now using a completely new solver. Let's assume the new solver fixes the issue. If not, please report to freecell-solver developers via https://github.com/shlomif/fc-solve