Sorry, Here's the first part.
NB.If a square, which one?
A=:'^<v>'
f=: 13 :'((|.|:|.4|+/~i.4),4|+/~i.4){y'
f A
v<^>
<^>v
^>v<
>v<^
^<v>
<v>^
v>^<
>^<v
B=:'<v>^'
((f A)-:"1 B)#1+i.8
6
((f A)-:"1 '<>^v')#1+i.8
Linda
-----Original Message-----
From: programming-boun...@forums.jsoftware.com
[mailto:programming-boun...@forums.jsoftware.com] On Behalf Of Linda A
Alvord
Sent: Wednesday, December 16, 2015 6:00 AM
To: programm...@jsoftware.com
Subject: Re: [Jprogramming] advent of code - day 3
Here's an approach to Santa's problem 3 for elementary school children:
NB. How many get more than one present?
T=:'v^^>^^^^v^^^^v^<v^^^vv^vvv^^vv<'
$T
31
h T
v^^
>^^
^^v
^^^
^v^
<v^
^^v
v^v
vv^
^vv
+/(0{"1 h T)=2{"1 h T
3
NB. Make lists to test squares
p1=: 13 :'(?(6+?y)#4){''^>v<'''
[U=:p1 28
v^<vv^>^v>>^^<<<v^v^^v^v>v<>
$U
28
Now write a verb to test for more than one present.
Linda
-----Original Message-----
From: programming-boun...@forums.jsoftware.com
[mailto:programming-boun...@forums.jsoftware.com] On Behalf Of Ryan Eckbo
Sent: Thursday, December 3, 2015 5:45 PM
To: programm...@jsoftware.com
Subject: Re: [Jprogramming] advent of code - day 3
I like these answers using complex numbers, nicely done.
On 4 Dec 2015, at 8:16, Jan-Pieter Jacobs wrote:
> This is mine (honestly without cheating ;) ).
> The notation of the complex directions can be very nicely written as
> subsequent powers of 0j1 : 0j1^i.4
>
> NB. 3) Number of houses getting at least one gift!
>
> NB. use complex numbers for directions
>
> NB. Every unique number is at least once on the list...
>
> s2a =: [: #@~. 0 , [: +/\ s2parse
>
> s2parse =: (0j1^i.4) {~ '>^<v'&i. NB. convert to complex
>
>
> NB. including robot santa
>
> s2b =: [: #@~.@, [: (0 ,+/\)"1 s2distrib NB. Same as above, per line.
>
> s2distrib =: [: |: _2 ]\ s2parse NB. distribute over Santa
> &
> RoboSanta
>
>
> i2 =: }: freads D,'input3.txt' NB. drop trailing
>
> 2015-12-03 21:21 GMT+01:00 Alex Shroyer <ashro...@gmail.com>:
>
>> Heh, I value sleep more than getting my name on the leaderboard...
>> plus I
>> was stumped until I read Reddit user Godspiral's solution <
>> https://www.reddit.com/r/adventofcode/comments/3v8roh/day_3_solutions
>> /cxldcnx
>>>
>> .
>>
>> I did enjoy how part 2 can be solved with just 3 more
>> strategically-placed characters. I really like *]\* as an
>> alternative to dyad *$* (reshape).
>>
>> On Thu, Dec 3, 2015 at 11:36 AM, 'Pascal Jasmin' via Programming <
>> programm...@jsoftware.com> wrote:
>>
>>> Winner solution, (but you didn't submit it at 12:18 :P)
>>>
>>>
>>> using complex encoding for pairs should probably always be done? It
>> makes
>>> your part 2 especially elegant.
>>>
>>>
>>>
>>>
>>> ----- Original Message -----
>>> From: Alex Shroyer <ashro...@gmail.com>
>>> To: programm...@jsoftware.com
>>> Sent: Thursday, December 3, 2015 11:25 AM
>>> Subject: Re: [Jprogramming] advent of code - day 3
>>>
>>> I was stuck at '^v<>'i.s , but came up with these after I peeked at
>> someone
>>> else's solution:
>>>
>>> part1=:#~.,+/\0,0j1 0j_1 _1 1{~'^v<>'i.s
>>> part2=:#~.,+/\0,0j1 0j_1 _1 1{~'^v<>'i._2]\s
>>>
>>> On Thu, Dec 3, 2015 at 8:59 AM, Joe Bogner <joebog...@gmail.com>
>>> wrote:
>>>
>>>> Mine:
>>>>
>>>> data=:fread 'advent2015/day3.txt'
>>>> getMoves=: ((0,1),(0,_1),(1,0),:(_1,0)) {~ ('^v><' i. ]) addStart
>>>> =: (1 2 $ 0) , ] smoutput answer1 =: # ~. +/\ addStart @:
>>>> getMoves data smoutput answer2 =: # ~. _2[\ ; +/\"2 (((0,1) $~ #)
>>>> addStart@,./.
>>>> getMoves) data
>>>>
>>>>
>>>>
>>>>
>>>> On Thu, Dec 3, 2015 at 7:00 AM, Ryan Eckbo <ec...@cim.mcgill.ca>
>> wrote:
>>>>> Data=. }: freads'/tmp/input.txt'
>>>>> houses=: 3 : '+/\ (0 0), (4 2$0 1 1 0 0 _1 _1 0){~ ''^>v<'' i.
>>>>> y'
>>>>>
>>>>> # part 1
>>>>> {. $ ~. houses Data
>>>>>
>>>>> # part 2
>>>>> santa=. 2 | i. # Data
>>>>> robo=. -. santa
>>>>> {. $ ~. (santa&# ,&shouses robo&#) Data
>>>>>
>> ---------------------------------------------------------------------
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