https://www.codingame.com/training/medium/minesweeper-1
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This retro viewer is simply priceless!!!
Can we vote for your next puzzle?
+1 for a FreeCell solver, aber natürlich in Win 3.x style… 
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FreeCell is an interesting puzzle and should be doable as a weekend project. I’ll put it on my list.
Usually I try to learn something new in these contributions. E.g. this one has a system clock which shows the real time and a debug view that re-scales a part of the screen instead of changing visibility. None of those is possible if you stick to the Java part of the SDK.
I have another project in mind but that’s going to be a complicated one and I’m not sure if I have the passion to do it. So FreeCell seems a nice filler when the other project frustrates me too much.
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Cool!
According to this article FreeCell problem has enough depth for multiple possible approaches, including GA, heuristics, etc. And most likely not brute-forceable in CG’s available solving timeframe.
Your puzzle made it in the last CG mailing, congratulations 
Mmm. I had a FreeCell implementation in the works.
Ok, FreeCell is all yours then.
Well, here’s a start: https://www.codingame.com/contribute/view/56162cb1ae8743fbda12c6b2eb519b8055a7
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someway a stupid question for sure … is there a way to put some flags or is it has to be memorized ?
sorry i just understood 
extremely funny !!! i got giggles during simulation specially for the hazardous heuristic strategy when no one of my real strategies occur… cheers ! *****
Got it at try 31 with the laziest AI ever 
I can assure you that success rates above 50% are possible 
Yes when I look at the games that failed there were obvious moves to be done but my algorithm goes like this:
- identify very obvious mines
- deduce very obvious non mines and play one
- if no obvious non mine, calculate probabilities of being a mine in the neighbourhoods of digit tiles, and play the tile with the lowest probability
- if no digit tile with unknown tiles in their neighbourhood, play a random tile that is not a identified as mine
I think the structure is okay but the problem is the first part, I identify a mine only when the neighboors match exactly the digit, but there are many other ways to identify a mine/non mine.
Example:
|???
|111
|…
Here obviously the third ? is not a mine cause there is a mine among the first two ?s so the midle 1 cannot refer to the third ?.
My algorithm doesn’t detect this kind of stuff at all, that’s why I called it lazy.
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Spoiler Alert: If you want to solve some of the situations you mentioned, you may want to check out this video https://youtu.be/cGUHehFGqBc?t=146
It’s no longer completley lazy, but not too much effort either.
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The hour displayed in the UI stays up to date ! 
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Thanks for noticing, I spent more time on this little detail than I should have.
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Hi guys!
It is a really nice challenge and I really enjoyed writing a code. But, does all challenges has a solution? For example, for this one Coding Games and Programming Challenges to Code Better I don’t know what the next move should be. If I’m not mistaken, every adjacent cell could contain a mine.
I don’t know but I guess they’re not guaranteed to have a logical solution, as in real minesweeper (it’s actually frequent that you have to guess once or twice in a game).
As for your example, it’s not as locked as it seems.
Let’s label tiles around your hole like this:
abcde
f...g
h...i
j...k
lmnop
g and i cannot both have a mine cause if they do, c, d, e can’t have a mine so the top-center 2 has only one neighbour left (b).
So it means that k has a mine and g/i share one.
For similar reasons, b has a mine and c/d share one.
Therefore, e has no mine.
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It took me the entire night to 100% it from scratch.
This should be an optimization game with scoring to compare our algorithms! 
Since Minesweeper is NP-complete, the best algorithm should be a SAT solver, which is sort of what I’ve done. Each slot of the board is a boolean variable which is true if there is provably a mine, and false if there is provably none. Each slot with a number of adjacent mines gives a set of clauses restricting the variables around. The goal is to prove that there is no mine (prove that a variable is false) before selecting the slot, or figure out some probability in the worst case.
The hardest part of course, was optimizing the data structure to avoid timeouts.
I can improve my algorithm further to win more often, maybe I will do it just for the solution contest.
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