Saturday, 27 June 2015

calculation puzzle - How to fill a honeymoon


       


How can a honeybee visit all cells exactly once in this crescent shaped honeycomb, beginning at the bottom tip and ending at the top?




  • The starting cell, at lower left, has 1 drop of honey. All other cells begin empty.





  • Each step consists of moving to an adjacent cell and filling it with 0, 1 or 2 honeydrops, based on how many total drops its (1 to 6) neighboring cells, combined, contain at that moment.




  • The number of new honeydrops is the remainder of the surrounding total when divided by 3.




$$\small \begin{matrix} \textsf{Total adjacent drops} ~&~ 0,3,6,9,12 ~&~ 1,4,7,10 ~&~ 2,5,8,11 \\ \textsf{Number of new drops} ~&~ 0 ~&~ 1 ~&~ 2 \\ \end{matrix}$$




  • The top cell, marked (1), is empty at first but should receive 1 honeydrop when it is reached.





  • The six cells with 0 should receive 0 drops when they are reached. (The sums of their neighbors’ drops should be multiples of 3 at those moments.) Other cells may also receive 0 drops.




No need to spoilerize a text solution. Site implementation makes that unduly onerous.


The following sequence of eight steps demonstrates how the bottommost 0 cell might be reached.



In this example, division by 3 comes into play when the last cell to receive 1 drop, on the seventh step, has a total of 1+2+2+2 = 7 drops in its adjacent cells, giving a remainder of 1 when divided by 3. The eight step correctly reaches the 0 cell as 1+2 = 3, which leaves 0 remainder when divided by 3.


This puzzle forthrightly, though incompletely, imitates Two honeycomb hints by Yuriy S.



This is meant to be convenient on paper and in a text editor.   Here is a template for

...
:



___
/(1)\___
\___/ \
\___/
/ \___
\___/ \
/ \___/
\___/ \___

/ \___/ 0 \
\___/ \___/
___/ \___/ \
/ 0 \___/ \___/
\___/ \___/ \
___/ \___/ \___/
/ \___/ \___/ 0 \
\___/ \___/ \___/
___/ \___/ \___/
/ 0 \___/ \___/ \

\___/ \___/ \___/
___/ \___/ \___/
___/ \___/ \___/ 0 \
___ ___/ \___/ \___/ \___/
/ 1 \___/ \___/ \___/ \___/
\___/ \___/ \___/ 0 \___/
\___/ \___/ \___/

And this is how the eight-step example could begin to resemble a maze:




\___/
___/ \___/
___/ 2 \___/ \___/
___ ___/ 2 ___ 2 \___/ \_
/ 1 \___/ 1 \ / 1 ___/ \___/
\___ 1 ___ 1 \___ 0 \___/
\___/ \___/ \___/

Answer



I noticed that things got a lot easier the more zeroes you are able to stick in there, and with that in mind, here's my solution:




Filled



Sorry it's not in text form, but I solved it on a tablet without a nice text editor. Lines between cells indicate where the bee has to travel.


If you'd like, I can update with a text version when I get to a computer, but I hope this is sufficiently readable on its own.


No comments:

Post a Comment