Can anyone help me find out what these kinds of puzzles are?

1. B&W Grid Puzzle

There's a grid with black & white blocks. A black block will turn white if it's surrounded by 3 white blocks. A white block will turn black if it's surrounded by 2 or 3 black blocks.

Example: If the initial shape is a "cross" made by 5 black blocks, what are the possible results given shapes A, B, C, and D? (See image below)

2. Foetus Puzzle

I can't remember exactly how this one works, but generally the contents of an animal's womb is determined by labels depending on the sex of adjacent foetuses.


If foetus A is beside 1 male foetus, A is labeled 1M.

If foetus B is beside 2 male foetuses, B is labeled 2M.

If foetus C is beside 0 male foetuses, C is labeled 0M.

They may be mapped out or have related questions, e.g. "What is probability of getting 1M 2M 0M?" or "If there are 2 males and 2 females, what constructions are considered impossible?"

3. Colored Grid Puzzle

There is a 3x3 grid and each square must be filled with a certain colour. There are 3 colours (red, green, and blue) to work with, but there aren't necessarily 3 of each.

Example: With the following statements, you have to guess which colour is in column 3, row 2.

1) The square in Column 1, Row 2 is red.

2) In Column 2, there are 2 green squares and 1 blue square.

... etc.


I couldn't recall the questions in detail but I hope I explained the type of logic puzzles I'm looking for.

puzzle examples

  • 5
    $\begingroup$ I don't know about 2 or 3, but your first example seems to just be a version of Conway's Game of Life $\endgroup$
    – Irishpanda
    Nov 30, 2015 at 21:17
  • 1
    $\begingroup$ I agree with @Irishpanda, the #1 appears to be a cellular automaton. We have a tag for those (cellular-automata) but it doesn't have much variety right now. $\endgroup$
    – f''
    Nov 30, 2015 at 21:36
  • $\begingroup$ Number 2 sounds like a variation of cellular automata, and number 3 kinda sounds like a variation of the game Mastermind, maybe? $\endgroup$
    – Irishpanda
    Nov 30, 2015 at 21:41
  • $\begingroup$ Thanks guys! It was really worth coming to this site:) BTW is there any special name for this kind puzzles? and where could I get more of these? Thanks again! $\endgroup$
    – jelly
    Nov 30, 2015 at 22:16

1 Answer 1


1 is Conway's Life, 2 I don't know, but it sounds like MineSweeper, 3 I think is this, but I don't know it's name:

enter image description here

The colours tell you how many of each colour are in each row/column, and are in the order red/blue/green/yellow, so they only tell you how many with no indication of position.

I am not sure if the solution is unique for this one, but here's one:

enter image description here

  • $\begingroup$ It is not unique, for instance, you can swap the first and second column. $\endgroup$ Sep 23, 2017 at 18:11
  • $\begingroup$ @CarlLöndahl; yeah i can see that! i might make top-left red as a gven...does it make it unique? $\endgroup$
    – JMP
    Sep 23, 2017 at 22:11
  • $\begingroup$ Nope, it doesn't :-) For instance, you can rotate the lower-right set of 4 squares (green-red) 90°. It is well within the limits of brute-force search. By simply enumerating the permutations of the columns (satisfying the upper restrictions) which is roughly, $(4!)^4$ give or take, you can count them all. $\endgroup$ Sep 23, 2017 at 23:12
  • $\begingroup$ @CarlLöndahl; so i should look for degenerate patterns. i would write some code, but i'm very busy at the moment with other stuff. the usual size of these puzzles is larger, say 8*8, so any code might get unwieldy. $\endgroup$
    – JMP
    Sep 23, 2017 at 23:16

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.