Bug 491558

Summary:	Solver declares "unable to determine if the game is winnable" for some Yukon games
Product:	[Applications] kpat	Reporter:	Mikhail Ramendik <mr>
Component:	solver	Assignee:	Stephan Kulow <coolo>
Status:	REPORTED ---
Severity:	normal	CC:	kde-games-bugs-null, shlomif
Priority:	NOR
Version First Reported In:	23.08.5
Target Milestone:	---
Platform:	Other
OS:	Linux
Latest Commit:		Version Fixed In:
Sentry Crash Report:
Attachments:	save file where game is "winnable" but every possible move causes "unable to determine"

Description Mikhail Ramendik 2024-08-11 01:02:55 UTC

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SUMMARY

In some Yukon games, Solver declares "Unable to determine if the game is winnable"; some of these games are winnable.


STEPS TO REPRODUCE
1. Open Yukon, deal number 1637567289 
2. Observe "Solver: Unable to determine if the game is winnable"
3. Move the 4 of hearts from stack 1 to stack 5
4. Observe "Solver: The game is winnable"
5. Move the king of spades from stack 3 to stack 1
6. Observe "Solver: Unable to determine if the game is winnable"

This happens in many other games but this example is easy to reproduce

SOFTWARE/OS VERSIONS
Linux/KDE Plasma: 
KDE Plasma Version: 5.27.11
KDE Frameworks Version: 5.115.0
Qt Version: 5.15.13

ADDITIONAL INFORMATION

Comment 1 Shlomi Fish 2024-08-12 10:35:28 UTC

Hi Mikhail!

From my experience in developing solitaire solvers, they use back-tracking, so sometimes exhaust their memory quota. https://en.wikipedia.org/wiki/Backtracking.

Comment 2 Mikhail Ramendik 2024-09-01 20:47:53 UTC

Created attachment 173217 [details]
save file where game is "winnable" but every possible move causes "unable to determine"

In this save file the solver shows "This game is winnable". However every possible move (as checked by the hint) moves to "unable to determine if the game is winnable". The game is winnable but one has to make some moves looking at "unable to detemine".