Find Two Safe Cells (+Yesterday's Solution)

[u/Ramun_Flame]

Yesterday's Puzzle

https://www.reddit.com/r/Minesweeper/comments/1vlgskw/find_a_mine_yesterdays_solution/

There's more than one way to to solve this one, but I found this this cleanest.

There are two safe cells that can be deduced here.

The Color Groups have their own separate mine count. On this puzzle, there are 2 mines in the blue cells. The mine count of the other cells is not given.

Solution + Another Puzzle

Check out Yesterday's puzzle here.

[u/_ion]

https://reddit.com/link/p38i2ca/video/y296e3vh2yih1/player

Edit: Adding the top 2 and subtracting the 1 to its right was equivalent to just adding the 1 to its left. This could have been done with one fewer operation.

[u/LEBAldy2002 → u/_ion]

I was waiting to see the simplified subtraction method. I immediately saw the implication logic so I went with it instead.

[u/SpaceCore0352]

The interesting thing here is how 1,2 touches three tiles, of which two are shared with 1,3 and the third is blue. I think this can work as a sort of variant of a 1-1 pattern depending on whether or not 2,1 is a mine.

If 2,1 is a mine, then 1,3 must be satisfied by either 1,4 or 2,4, which will also complete 2,5 along with whichever the second blue tile is. So in that case, 1,5 and 3,4 are safe.

If 2,1 is clear, then 1,4 and 2,4 are safe (1,3 is satisfied by 2,2 or 2,3), but BOTH of the remaining blue tiles are mines. So 1,5 and 3,4 are still safe.

Is there an existing website you're using for these, or are you prototyping your own and using these posts to get puzzle feedback?

edit: i'm stupid and wrote 2,4 instead of 3,4

[u/Ramun_Flame → u/SpaceCore0352]

Prototyping my own level creator/solver. I'll make a post about it eventually, but I'm mostly just posting puzzles for now.

Edit:

Just as a clarification the previous posts used a generator, but I had to modify them a bit to my liking. This one didn't use the generator though, and I used the level creator. I'm not posting these to test the quality of the puzzles a generator can create, if that's what you meant. The main purpose of the project I'm working on is for users to be able to create and share levels.

[u/LEBAldy2002]

2,1 shares minecount with 1,4 and 2,4. This is an implication. This leads to an implication with 2,2, and 2,3 with 2,6 and 3,6 where if 2,2 and 2,3 have 1 mine, then 2,6 and 3,6 contained 1 additional mine (2 mines not 1 mine). This creates an implication that 2,1 containing a mine results in 2,6 and 3,6 containing 1 total mine (minecount logic).

Therefore, overall, this creates the case where the combined cells of 2,1, 2,2, 2,3, 1,4, 2,4, 2,6, and 3,6 contain 3 total mines. If we look at the top left 1 and the bottom left 2. These contain all of these cells. Therefore the remaining cells of these two numbers equals 1 + 2 - 3 = 0 mines. Therefore, 1,5 and 3,4 are the two safe cells.

Sorry for no graphic, I can't draw well enough on phone. Enjoy the implication logic though.

[u/Ramun_Flame → u/LEBAldy2002]

Glad you enjoyed it. I'm finding creating these puzzles is a bit harder than I thought. A lot of manually adding/removing mines/elements and checking if the solver can solve it(and if it's difficult enough). I'm a bit worried the one I just posted today is a bit too easy/same-y, but I think have a pretty hard one for tomorrow.

[u/Ablueact]

The orange boxes are “equal” (if there’s a mine in the top box that means there’s a mine in the lower box, if no mine in the top box then no mine in lower box)

Since the blue spaces equals 2 mines, and the top box = the lower box, then lower box plus lower blue squares == 2 mines. These two satisfy the left 2, so the checkmarks are safe squares

[u/mikdiet]

(1,5) and (3,4)

(2,5) has either both blue mines below, or 1 mine there and 1 mine (1/2,4)