There is one Enigma puzzle this week, "Rainbow Adjacencies" by me.
(Note that there is still a bit of time left to submit solutions to last
week's puzzles. I also deleted all the submissions by accident; I've
managed to recover which order they were submitted in, but not their
content (stupid bham.ac.uk undelete being buggy). Could people who
submitted a solution to them please forward it to me, if they haven't
already? As a result, last week's results are coming later. AFAICT,
Enigma is unaffected by the Holiday as it's a contract, not a Rule.)
Here's the puzzle:
On Sat, 2008-12-27 at 19:35 +0000, Alex Smith wrote:
> I submit the following Enigma puzzle, titled "Rainbow Adjacencies":
>
> Question:
> {{{
> Suppose you have a 5 by 5 grid of squares (i.e. 5 squares across, 5
> squares down, sort of like a chessboard but smaller). Two squares on
> this grid are 'adjacent' if their x-coordinates differ by 1 and their
> y-coordinates are the same, or vice versa (i.e. adjacency is orthogonal
> but not diagonal). Also, the grid is considered to wrap round; two
> squares can also be adjacent if their x-coordinates differ by 4 and
> their y-coordinates are the same, or vice versa.
>
> To solve this puzzle, you have to colour each square on this grid Red,
> Orange, Yellow, Green, Blue, Indigo, or Violet (different squares can be
> different colours), whilst obeying the following restrictions:
> 1. Each of the 7 colours must be used at least once; that is, for
> each colour, some square on the grid has that colour.
> 2. The regions of each colour must be connected. In other words,
> for any two squares which are the same colour, there is a
> (possibly empty) path of squares of that colour connecting them,
> such that each pair of squares along that path are adjacent.
> 3. For any two colours, some square of the first of those colours
> is adjacent to some square of the second of those colours.
> In other words: you have to separate this 5x5 grid, with 25 squares,
> into 7 different regions, each a different colour, such that each of the
> regions is connected, and each region borders each of the others.
> (Restriction 3 is the hard one, of course).
>
> As an example, I give a solution to a similar puzzle using a 3x6 grid
> and only 6 colours:
>
> RRROOO
> YYGGGY
> BIIIBB
>
> Good luck doing it on a 5x5 with 7. I'll look forward to your solutions.
> }}}
Scoring is the same as always; 8 points for the first correct answer, 4
points for subsequent correct answers, no penalty for a wrong answer
(subject to the restriction that if you submit more than one correct
answer, only the first one scores; a correct answer after a wrong answer
can still score, though). You don't have to be a member of Enigma right
now to play; just join while the answer submission period is running,
and make sure you're a player of Agora when I award points, and you can
participate and score too.
You have one week. Happy puzzling!
--
ais523
